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Feature Article: 


Teacher Change: : 
Philosophy & Technolt ; fi 





Reviews: 


Caddman Cadet 
Pacific Powernet 





Conference Papers 


PLUS..... 


Logo for maths tools 


Using CD-ROM systems 





Standard International Signs 


Gi 








Registered by Australia Post Publication # NBP5123 


-omputer Education Group 


Editorial 

FEATURE ARTICLE 

TEACHER CHANGE: Philosophy & 
Technology HelenMcDonald 3 | 


CAL : WHATS IN A WORD ? : 
Melissa Nursey-Bray & Karen Reys 9 |. 


Standardized International Signs 16 : 


Can You Write Me Some Tools That... : 
Clive Lynn 17} 


DELTA: Design Environment for _ : 
Learning Top-Down design for Algorithms}. 
Trevor Barrett 27} 


The Use Of CD-ROM Systems : 
Leonie Fraser 35 |. 


Pacific PowerNET :A resource for 
teachers. John Attwood 


Review of Caddsman Cadet : 
Greig Tardiani 41 | 


Editor 
Neville Fraser 
Publicity 
Leonie Fraser 





ISSN 0813-4871 





Information Transfer Term 3 - 1993 


2 Term 3 - 1993 


New South Wale 





Welcome to this the third issue 

of IT for 1993. The more 

observant of you will have noted 
that this is a bit late in the year. Please rest 
assured that Issue Four is coming quite close 
behind, and you will get all four issues for the 
year! 


I think everybody has had a busy year, and the 
workload of teachers and lecturers has increased 
disproportionately to any increase in support. The 
expectations of implementing new syllabi*, 
quality assurance, and the spectre of “structural 
change”, as well as a widespread ‘flu epidemic, 
has made for a difficult time. 


This is an issue of IT with a bit for everybody, I 
feel. We again include a feature article, this time 
letting you consider your "philosophy" in 
computer education. This is a point that I feel 
strongly about, inflicting a lecture to my trainee 
teachers each year! See how it effects you. . 


What about some high level Logo programming? 
There is an article from the LOGO '93 
Conference in Melbourne. No doubt it will have 
maths teachers getting excited! 


Not all the good material from the National 
Conference was able to be included in the 
Proceedings or Journal, so we will be printing 
some of it over the coming months. This issue 


there is our feature article, plus items on CAL and 


an alternative to traditional 


programming. I hope you get something 
out of them. 


Finally, there are our reviews. I always like to get 
reviews from you, as they form a very useful link 
between what the suppliers think is good for you 
and what academics think you should be able to 
do. If you've tested out some software or 
hardware, let us know about it. Even a single page . 
is fine. 


One of our reviews this issue is very special. I 
was lucky enough to be at the launch of 
Powernet, which has the potential of being a very 
powerful resource. I do have some reservations at 
present, and I admit that the style of the launch 
left a lot to be desired as far as I'm concerned, but 
I'll not shoot the thing down before it starts. 


The Department is putting together a Computing 
Studies Intensive Methodology Course which will 
be piloted early next year. I have been part of the 
design team working on methodology. It is good 
to see the various teachers, consultants and 
lecturers getting together nut out a course like 
this- its's not before time! 


Next issue? How about some video reviews, more 
NatCon papers, more Logo, and some Christmas 
treats? See you then! 


Neville 


MEMBERSHIP RENEWAL 


WOW ca the time to renew your membershi~p 


for 1994/1 


AAU membenchifr renewed before MARCHA let 1994 
neveiue a $10 voucher redeemable as a discount 


againet CEG products. 





Information Transfer 


Computer Education Group 





TEACHER CHANGE: PHILOSOPHY AND 
TECHNOLOGY 


Helen McDonald 
Methodist Ladies' College, Melbourne 


ABSTRACT: 


Computers and their related technology may be 
relatively new to the educational scene, but the 
process of change is not. Persuading people to 
change is rarely an easy task. Change can seem 
threatening, it can bring insecurity, anxiety and a 
great deal of hard work. The process of change is 
personal and time-consuming, requiring 
commitment and support. Thus to embark on 
what may be a difficult process (and perhaps a 
Stimulating and exciting one) requires a 
conviction that the journey will be worth it - a 
belief that the outcomes are worth achieving. 


This paper looks at the relevance of a firm 
philosophical foundation as a basis for 
technological change. It also notes the importance 
of action-research in re-assessing the purposes, 
beliefs and practices of teachers. Much of the 
research referred to relates to a case study of 
Methodist Ladies’ College, Melbourne, where a 
program based on independent learning and 
utilizing laptop computers has been operating 
since 1990. 


Change can be achieved on many levels, from a 
superficial adoption of a few visible facets, to a 
complete assimilation of the change which 
challenges and alters old structures and existing 
beliefs. Real change must go below the surface, 
beneath the adoption of hardware and software, 
beyond the acquisition of new skills. For teachers 
it means looking at learning and re-examining its 
processes. 

I need three more days in the cycle to be able to 
get through all of this! I feel like | can never do 
anything properly: I’m just skimming over the 
surface. | haven't got time to read what I need to 
read and I haven't got time to digest it. Look at 
this pile of work I have to get through! 

Please - no more change! We haven't got 
through the last one yet. | need to have time to 
think about what I am doing instead of changing 
it every five minutes! 

{M_L.C. teacher Feb. 93) 


Information Transfer 


To many teachers, frequent change is not an 
attractive proposition. It is too demanding, too 
exhausting and often doesn't seem worth the 
effort. Change takes time and it often requires the 
relinquishing of control. No wonder that some 
teachers prefer to "cultivate their gardens’, 
changing things they can control - small pieces of 
the syllabus; additions to a program - safe 
innovations that are manageable. (Huberman, 
1992, p.5) By so doing they avoid the roller- 
coaster ride of major change which may 
exhilarate one minute, and plunge innovators to 
the depths of despair the next. 


At Methodist Ladies College in Melbourne, the 
roller coaster ride 1s mandatory for all staff. The 
climate at this school is demanding but it also 
encourages risk-taking, supports innovators, 
invites experimentation, copes with mistakes/ 
problems and celebrates achievement. Envisioned 
as "a learning place for teachers as well as 
students" (Loader, 1993, p.6), M.L.C. seems to 
have developed an institutional capacity to 
innovate. Coping with change appears to 
improve with practice and many of the existing 
staff are well-versed in the process. The 
administration both supports and encourages (or 
some May Say pressures) active participation in 
innovative programs and has established formal 
networks to facilitate change. That is not to say 
that all change at M.L.C. is successtul, nor does it 
come without the associated "pain and disorder” 
which are "healthy signs" of school improvement. 
(Huberman, 1992, p.6) 


The particular change upon which this paper 
focuses is one of many occurring at M.L.C. and 
should be seen in that context. The innovation 
centres upon constructionist thinking and the 
encouraging of effective independent learning at 
Junior Secondary level (Years 7 and 8), although 
both concepts are not exclusive to this section of 


Term 3 - 1993 


4 Term 3 - 1993 


the school. Linked significantly to this 
philosophical base is the integration of laptop 
computers and the use of LogoWriter. 


The Principal, David Loader, speaks 
enthusiastically of M.L.C’s move towards a more 
constructionist approach, which centres upon the 
individual student's learning: 


This approach is based upon Piaget's 
"constructivism" where knowledge is "built by the 
learner, not Supplied by the teacher." This idea 
has further been extended by Seymour Papert to 
“constructionism" which includes "the further 
idea that this happens especially felicitously when 
the learner is engaged in the construction of 
something external or at least shareable ... a sand 
castle, a machine, a computer program, a book." 
(Polin, 1990. p.6) 

The idea of knowledge being constructed by the 
Student shows appropriate respect for the intellect 
of the learner and reflects the subjective, and 
evolutionary view taken of knowledge. The 
student, in such a view, is not a passive recipient 
of data but a constructionist trying to understand 
her world, having meaningful experiences, 
making personally — significant connections, 
developing mental models, collaborating with 
others in an enriched teacher supported social 
setting. 

(Loader, D. 1993, p.4) 


New South Wale: 


peers is more "inter-dependent” and co-operative. 


Computers and other forms of technology, were 
seen as having strong potential in assisting the 
implementation of these beliefs and so were 
introduced concurrently. In 1989 a pilot class was 
taught by a team of three, following the ethos of 
independent learning. Four computers were 
located in the classroom as a resource and the 
program LogoWriter, was used. 


In 1990, four Year 7 classes took the innovation 
on board, with one class using laptop computers. 
School policy requested that each student in this 
Class own their own laptop computer at an initial 
cost of approximately $1,500. The success of the 
project and subsequent parent demand saw nine 
out of 10 classes in 1991 and 1992 using laptops, 
while the remaining classes had daily access to 
the computer network. In 1993, all year 7 students - 
use their own laptop computer. LogoWriter has 
been integrated into English and the Humanities 
(History, Biblical Studies and Geography), 
Mathematics, Science. and some L.O.T.E.. In 
teacher terms, the team expanded each year, 
attracting like-minded staff until the change 
became policy and all Junior Secondary teachers 
became involved. 





In M.L.C.'s Junior Secondary School, this view 
became woven into the philosophy of 
independent learning. The aim was to create a 
learning environment which highlighted 
individual differences rather than suppressing 
them. Students were encouraged to work 
effectively without constant direct instruction. 
They could set their own working pace, have 
some flexibility in areas of study, and pursue 
options which motivated them - all within a 
framework provided by the teacher. "Learning 
experiences" were emphasized rather than 
"teaching programs” as students were encouraged 
to take responsibility for their own learning. Their 
role became more active: observing, participating, 
working together, constructing and reflecting . In 
fact, "independent" learning is perhaps, a 
misnomer as the relationship with teacher and 


Many people both within and outside the M.L.C. 
community tended to view the highly visible 
laptops as "the change". Some labelled it as a 
"gimmick" or an "enrolment booster” - part of a 
technological bandwagon that would provide a 
clear advantage to those who were a part of it. 
However, those who initiated the program would 
argue that the laptops were introduced only to 
facilitate and enhance the possibilities created by 
independent learning. In many ways, laptops were 
not the change: the change was in thinking, in 
learning and in teaching. The technology 
supported the change as a rich resource. 

As one M.L.C. teacher stated: 


You can't put a kid in a classroom with a laptop 
and LogoWriter and expect miracles to happen. 
The computer itself doesn't do a thing for you. It 
needs someone to make it happen, someone to 





Information Transfer 


Computer Education Group 


give you Ideas. It needs a philosophy of how and 

why we are doing it - it needs an aim. It needs 

people who know how to go about achieving it. 
(Interview: 2/4/92) 


And so the teachers who worked in the Junior 
Secondary School had to assimilate the views of 
constructicnism and independent learning with 
their own personal educational outlook. For a few 
- particularly the initiators who were involved in 
the pilot program - the philosophy, the technology 
and their own educational outlooks were 
compatible from the outset. For others, the task 
was not SO easy. 


Some accepted the philosophy, but shied away 
from the laptops and the technology entailed. 
Others embraced the computers, seeing the 
technology in terms of professional development 
and as a means of enhancing their teaching. A 
third group wished only to continue “cultivating 
their gardens", and tended to accept the trappings 
of the change without significantly altering 
practice. 


However, there does seem to be a point where 
these pats ¢ can melee Once teachers have come 





to grips with the more operational aspects of the 
change (whether it be computers or independent 
learning) , they begin to build the mental models 
necessary to provide inroads into the other aspect 
of the change. For example, the teacher who 
embraces computers soon comes to realize that 
students can and do work more independently 
with the laptop. The flexibility provided in 
recording, generating and presenting information 
allows students more scope. The medium also 
seems to encourage more frequent interaction 
among peers - such as group problem solving. 


Whether intentionally or not, the teacher's role in 
the classroom changes. No longer the expert, the 
teacher must learn to facilitate. No longer the 
instructor, the teacher guides. The philosophy of 
independent learning becomes relevant and the 
reality of the classroom makes the connection 
between beliefs and practice. 


Information Transfer 


Alternatively, for those who believed in the 
philosophy, the value of laptops and LogoWriter 
quickly becomes apparent. As students use 
LogoWriter in most subjects, they begin to utilize 
its functions across subject boundaries. Teachers 
do not need a great deal of technical expertise to 
allow the laptop to be used as a tool in their 
classes. They do not need to be master 
programmers to mark a piece of work on disk. As 
they see the technology assisting students with 
organization, drafting and problem solving, it 
quickly becomes apparent that its link with 
independent learning is a valid one. 


The third group, teachers who are resistant to the 
change, can be quite successful in limiting 
changes to practice but only for a short time. As 
students become skilled with the technology, they 
begin to use it in all subjects. A teacher who does 
not encourage computer-use soon becomes visible 
and has to deal with a situation where students 
expect consistency of approach both in classroom 
operation and learning style. Students do not react 
well to a student-centred approach in five classes 
and the traditional teacher-centred approach in 
one. 


This reticent teacher group, although not 
experiencing the changes first hand, can not fail 
to observe the educational outcomes as they 
become apparent. Subject meetings soon include 
frequent demonstrations of successful programs 
generated by colleagues; the staffroom 
conversations introduce the jargon associated 
with both constructionism and computers and the 
administration begins to insist that all reports are 
generated using a computer. As the culture of the 
school alters, those who avoided the change feel 
increasingly “left behind”. 


To meet the needs of all teachers, a support 
system must continue to provide opportunities for 
staff to tap into a learning network which allows 
participants to obtain new knowledge and skills as 
the need arises. Gary Stager (Interview: 1991) 
described it as "casting small nets” - to encourage 


Term 3 - 1993 


771 


6 Term 3 - 1993 


teachers, at the point where they feel ready, to 
“have a go" and to be part of the emerging 
culture. New staff entering the school must also 
be catered for, as they bring with them knowledge 
and skills which may further build the culture, but 
may also need support to acquire the skills 
necessary to teach in the established program. 


This process where the divergent paths tend to 
converge may be illustrated diagrammatically: 


nie to the change. 
| Teachers: 


motivated by 
Computers 


Initiators with strong 
beliefs in: 


1) Indep. Learning & - 





A teacher culture based on the 
philosophy of constructionism 


and independent learning, and 





Constructionism utilizing technology to support 
2) Technology these aims. 
Teachers: 
motivated by 


essai New teachers 
entering the school. 





Hence, although the school succeeded in 
providing a solid and appropriate philosophical 
foundation for the introduction of technology, 
teachers often had to work with laptops and 
within the new structures - forging their own links 
and meanings. As Fullan (1992: p. 25) states ° It 
seems that most people do not discover new 
understandings until they have delved into 
something. In many cases, changes in behaviour 
precede rather than follow changes in beliefs.” 
Some teachers also need to see outcomes 
emerging before committing themselves 
personally. 


The importance of "beliefs" and "understandings" 
is central to the success of a change process. As 
Michael Fullan states: 


All substantial innovations have underlying 
beliefs, rationales or — philosophies...(Those 
involved will ) have to come to understand and 
believe in the new assumptions and ideas that 
underline that reform. 9 

Fullan, M.G 1991, p.2 


However, the point in the change process where 
that meaning is obtained is not set or fixed. If a 
school's philosophy is based on constructivism, 
then teachers too must be encouraged to build 

their own mental models and develop their own 
meanings and beliefs. This includes the active 

provision of experiences which confront theory 


New South Wales 





and allow for the evaluation and re-evaluation of 
aims and purposes. As teachers conduct and share 
their Own action-research, meanings can be 
exchanged and a culture extended which includes 
and accepts the experiences and beliefs of all 
participants. 


In such a learning environment one needs to see 
learning philosophy as fluid and as changing. Just 
as teachers are influenced by the provision of a 
set of beliefs and concepts, proposed as a 
foundation for teaching and learning, so does 
their experience influence and alter the 
educational philosophy. Action-research may 
result in the extension of ideas, changes in 
emphases, the rejection of some concepts and the 
integration of others. And so the cycle of theory 
and practice continues, constantly evolving. 


Educational philosophy 


which underpins the = te 
Share of ideas and concepis 
leads to re-evaluation of 


Direct experience: . 
purposes and, in turn, alters 


the base philosophy. 


Mi of own dit 


beliefs and mental modelb. 


Learning & doing 


Fullan and Miles (1991) describe “change” as "a 
process of coming to grips with new personal 
meaning ... a learning process.” It requires the 
participants to alter their purposes, develop 
commitment to new ways and to “unlearn old 
beliefs and behaviours." (Fullan and Miles, 1991. 
pp10-12) As such it requires great effort from 
individuals who must cope with anxiety, 
difficulties and uncertainty as they seek , not only 
to introduce an innovation but to change the 
culture of their schools. 


To embark on major change - to take on board 
new ideas and skills is demanding. Change takes 
effort and a great deal of commitment. Anxiety, 
uncertainty, frustration, overload, lack of skill, 
complexities, incompatibility: all were 
experienced in the M.L.C. study. The process of 
change is not easy as the comments below 
indicate: 

It was the most frustrating thing I've ever been 
through. There was a lot of expectation placed on 
teachers ... the approach was made compulsory, 
but where do you find the time to build new 
skills? It was assumed we would do it, assumed 
that you would understand and be able to cope - 





Information Transfer 


Computer Education Group 


but some people did not understand and some 
didn't cope and some didn’t really try. 
(Interview 6/12/91) 


It’s exciting, but you wonder how long people 
can maintain this enthusiasm and commitment... 
you wonder how long teachers can keep up the 
pace and the pressure. The environment for the 
kids is fantastic - they have exciting experiences, 
computer experiences and all that. But the 
teacher workload is very, very high. 

(Interview 19/3/92) 


If the process of change is to be experienced as 
accomplishment rather than frustration, a strong 
sense of purpose needs to be accompanied by 
many practical considerations. 


As Linda Darling-Hammond writes: 


..the process of change is slow and difficult. It 
requires perseverance, and it — requires 
investments in those things that allow teachers, as 
change-agents, to grapple with the 
transformations of ideas and behaviour: time for 
learning about, looking at, discussing, struggling 
with, trying out, constructing, and reconstructing 
new ways of thinking and teaching. 

L. Darling-Hammond 1990 p.240 


In practical terms M.L.C. did much to support 
staff with workshops, rebates for computer 
purchase, educational courses, classroom support, 
access to information and a network of people 
who could provide assistance. 

Most activities were voluntary and repeated, thus 
allowing staff to join in when the experience 
would be most meaningful and/or convenient. 


One of the most worthwhile professional 
development options was the running of 
residential workshops, which took staff away 
from their usual commitments and provided the 
time “to play" with LogoWriter and discuss 
philosophies of learning in a supportive 
environment. As well as formal structures, 
personal networks emerged, through which 
teachers could obtain information without feeling 
anxious or incompetent. 


Support must be planned for, but it must be 
flexible enough to serve a variety of needs at the 
same time. As needs change and new demands 


Information Transfer 





are made, so support structures must adapt, for it 
is only after attempts are made to implement 
change, that we come to understand more clearly 
what we need to know. 


Teachers, like all learners, should be given the 
Opportunity to make sense of change. Whether a 
philosophy of learning and teaching, or a 
technology- based innovation, staff must be 
allowed to experiment, to make mistakes, to 
explore and to discover. Structures need to be 
developed which allow for the free exchange of 
ideas and experiences in a supportive 
environment. 


The initial motivation to participate in change 
may come from many directions, but a climate 
should exist where participants can feel that their 
involvement in the change has purpose and will 
provide benefits. 


To ensure relevance and a valid framework for 
change, the existence of a clear philosophy needs 
to be shared with those involved. Nor should the 
change or the philosophy be viewed as a Static 
package which is to be "learned" or implemented. 
Meanings and beliefs need to emerge through 
experience and practice: they need to be shared 
and they need to be challenged. 


Encouragement can take many forms but, as ina 
financial transaction, people need to be able to see 
a definite return for time and effort invested. 
Learning outcomes need to be monitored and 
recorded, changes in relationships and roles need 
to be discussed - and adaptation must occur as 
needs dictate. In this regard, the role of action- 
research is critical to ensure that theory and 
classroom reality support each other. 










Helen McDonald, a secondary English teacher 
and currently a Ph.D. student from Monash | 
University, has been conducting research at | 
Methodist Ladies’ College, Melbourne in the | 
field of educational change. i 


Term 3 - 1993 7 


New South Wale: 





REFERENCES: 


Darling-Hammond, L. (1990) Instructional Policy Into Practice: The power of the bottom over the top, 
Educational Evaluation and Policy Analysis: vol. 12 no 3 Fall 1990 A.E.R.A. pp. 233-252. 


Fullan, M. (1991) Overcoming Barriers to Educational Change. University of Toronto: Paper 
commissioned by the Office of the Under Secretary of the U.S. Dept. of Education. 


Fullan, M. (1992) Successful School Improvement. Open University Press, Philadelphia. 


Fullan, M.G. and Miles, M.B. (August 1991) Getting Educational Reform Right: What works and what 
doesn't. Submitted to Phi Delta Kappan. 


Huberman, M. (1992) Critical introduction to Fullan, M. (1992) Successful School Improvement. Open 
University Press, Philadelphia. pp. 1-20. 


Loader, D. (1993) Reconstructing an Australian School. submitted to The Computing Teacher. 


Polin, Linda. (1990) What's hot and what's not. The Computing Teacher. August/September. 


ACCE ‘93 Proceedings 
PLUS 
Conference Issue of the Journal 
TOGETHER!!! 
$50 (includes postage) 


Available from: 


NSW CEG Ltd, 
c/- TEP Instructional Technology Centre, 
School of Education, 


Macquarie University, 
NSW 2109 


8 Term 3 - 1993 Information Transfer 


Computer Education Group 





CAL: What's in a Word? 


Melissa Nursey-Bray & Karen Reys 
Cairns College of TAFE 


INTRODUCTION Cairns College Of TAFE, James Cook University 
The relationship between computer technology and the Queensland Open Learning Centre 

and education has developed to enhance delivery Network (QOLCN). 

and learning programs. Nowhere is this most 
evident than in the field of remote and distance 
education. One particular development in this 
area is the use of CAL. (Computer Assisted 
Learning) packages. The use of these programs 
has advantages and disadvantages. This paper will 
discuss some of these within the context of the i wk 
Community Ranger Training program and communities. It also allows Aboriginal and 
Remote Area Teacher Education Project Torres Strait Islander participation in decision 


(RATEP) of the Cairns College of TAFE where making through their representation on the 
CAL has been used extensively. Discussion will Curriculum wane Advisory Committee, 
first centre on the use of | Fm = ac usteiaisbemnsesnearaomei ie! ,, the Management Committee 
CAL by RATEP, i ee : : i land the Reference Group. 


concentrating on how 
CAL works, and how its 
use developed at the 
Cairns College of TAFE. 
The second part of the 
paper will examine A. 3 
aspects of CALs’ use in & : eerie eter temermmnnernensnrermemerortt 


 % eames These are 
the field with particular jf | ese etatelatec 6 ake 7 seen es 2 .Limportant BOS A addressing 
reference to the ; ; Pays ie Figs Biggs caren oe 


1 - the problems of remote area 
Community Ranger 


Training program. 


The program evolved in response to the need to 
enable Aboriginal and Torres Strait Islander 
people to attain the same qualifications as non - 
indigenous teachers. It thus performs a vital 
function in allowing students to attain teaching 
qualifications without having to leave their 






ee ae 














; There are over seventeen on | 
| packages used by RATEP in § 
it delivering their courseto 3 
communities 


# The use of CAL within this 
be : context provides equity and 
© ‘ ; _access in education. It also 
~~ Supports self paced and 


of self esteem 
| een The re a ae eres el ente CAL packages used b 
RATEP: REMOTE AREA deat ea tag ee 
RATEFP in delivering their course to communities. 
TEACHER EDUCATION These include literacy, and teaching packages 
PROJECT which use community examples and relevant 


contexts to develop concepts. RATEP has also 
developed information packages on its course and 
one which explains CAL and its functions. 


RATEP provides teacher education by remote 
delivery to Aborigines and Torres Strait Islanders 
living on remote communities in the Cape York 
and Gulf regions. It offers at seven sites (ten by 


the end of 1993) an Associate Diploma of HOW CAL WORKS 

Education (Community Teaching). Students can CAL packages are delivered to the sites on 44 
then continue through RATEP to undertake the megabyte removable cartridges (PLI/Syquest) and 
second year of the Diploma of Teaching with then loaded onto a hard disk through a PLI drive. 
JCU. RATEP is aco -operative effort between While still in use, the overall aim of RATEP Is to 


Information Transfer Term 3 - 1993 9 


10 Term 3 - 1993 


offer CAL through use of CD - ROM, which is 
easier to develop as CAL can then be directly 
programmed onto the CD. Benefits of this will 
include greater storage Capacity, and therefore 
highlight the benefits of CAL. These include 
greater video, graphics and extra sound effects. 


CAL is created by computer programmers who 
develop the packages from the material given to 
them from course writers. Authorware 
Professional; which is a multimedia software 
package using Macintosh based hardware, is used 
as the foundation for development of CAL. A 
CD Rom is used to add music to the packages due 
to the quality of sound that this offers. A colour 
scanner 1s used to include photographs, and 
colour graphics and designs for the package. 
However, colour and sound take up much space 
and thus their potential has not yet been realised 
as student machines have lesser megabytes. 
available. 


Macromind Director while used as an animation 
tool is also not used extensively as it is not 
possible to use Macromind Accelerator in 
conjunction with Authorware. The inclusion of 
video is likely to be an alternative to this process. 
Quicktime and a RasterOps Board provide 
programmers with the opportunity to incorporate 
short video segments within the CAL package. 
The most recent RATEP package has been able 
through the use of Quicktime video, to use action 
shots to teach court procedures and other things. 


CAL is simple to operate once the user is familiar 
with its mechanics ; students are asked to push a 
button, use the mouse to drag items over, type in 
text, use the menu's or listen to and observe the 
information presented. The student can then 
respond, try again, go back to Start, quit or be 
corrected. A series of encouraging icons and 
noises are used to facilitate student interaction. 
These include clapping noises, cheers, happy 
music, or verbal/written messages such as "Very 
Good!" 


CAL: CURRICULUM 
DEVELOPMENT AND DESIGN 


CAL is used to respond to the educational and 
developmental needs of the students and the 
learning objectives aspired to by the course 


New South Wales 





writer. Ideally, this requires a good interaction 
between course writer and programmer to ensure 
the succinctness of such response. Within 
RATEP this has not been a problem as there is 
close communication between the two, and the 
course writers have been aware of the needs of 
students on community. However, where these 
needs are not perceived, (as is sometimes the case 
if a course writer is external to the program), the 
CAL design accordingly, may not fully explore 
its potential for the subject, or remote educational 
requirements. 


An important aim of CAL is to encourage self 
paced learning. Course development and design 
therefore is in line with this objective. The 
interactions that can be developed are many, and 
if designed carefully, curriculum objectives can 
be met through them, without putting pressure on 
the students. RATEP has put together a course 
writing outline for coursewriters to facilitate this 
process. 


By and large a serendipitous approach to design 
has been adopted where; time constraints 
notwithstanding, programmer and course writer 
together create an effective program, with 
adequate feedback choices and covering the main 
points. This approach has ensured a creative 
outline for each package, and allowed a freshness 
to each amalgam. The flexibility in presentation 
that CAL offers, is one of its key actractions, 
especially as there are many avenues to yet be 
explored. 


Characteristic of CAL within this context is its 
ability to present different learning pathways. 
These may be linear, cyclical, random or 
according to student choice. For example, it is 
possible for the student to enter the package and 
continue in a linear fashion until the end. Or it is 
possible to choose between a series of options, 
and click on one of those. These options may 
develop in a cyclical fashion ie. coming back to 
the same point at the end, or may just finish and 
allow the student to choose the next one. The 
parameters of these pathways, especially cyclical 
have not as yet been explored to their full 
potential in terms of relevant and innovative 
learning strategies. Nonetheless, CAL compares 
favourably to other educational packages such as 


Information Transfer 


Computer Education Group 





Hypercard that are limited in the pathways they 
present, and thus their interactions. 


It is clear then that CAL offers various 
opportunities for educational development 
previously ill utilised. Used in the field, CAL has 
differing levels of success, and it is to its 
problems and advantages in remote education in 
particular that we now turn. The Community 
Ranger Training program is a good case in point. 


COMMUNITY RANGER 
TRAINING PROGRAM 


The Community Ranger Training program 
delivers a Certificate and Advanced Certificate in 
Cultural and Natural Resource Management, and 
an Associate Diploma in Applied Science. The 
course is delivered to over seventeen 
communities. These include the Gulf 
communities, Northern Peninsula communities, 
East and Southern coast and Wet Tropics 
communities. 


The Diploma consists of twenty modules and has 
been developed in response to requests by 
Aboriginal Community Councils through the 
Aboriginal Co -ordinating Council. These 
communities identified an urgent need to become 
actively involved in land management and site 
protection. Community Councils have since 
undertaken to employ trainee rangers. This course 
offers trainee rangers the opportunities to gain 
many skill appropriate to their need. 


The Associate Diploma of Applied Science 
although one of three levels of attainment, is the 
only one in which CAL. has so far been used. . 
Anthropology and Archaeology , Politics and 
Change , Introduction to Management, Australian 
Plants and Animals. and wildlife Management 
are all subjects that have utilised CAL packages 
to varying degrees. This list illustrates that CAL 
packages can be applied in a variety of contexts. 


CAL IN THE COMMUNITY 


There have been many positive reactions to the 
CAL. package from the students. This has been 
because the interplay between the screen and the 
person doing that package is quite personal. The 
CAL package does not rush one, and it does not 





Information Transfer 


put pressure on the student. 

In some cases this has been good when a student 
has a learning disability and needs to take time 
over his/her answer. The student is the one the 
computer will interact with. Therefore if a student 
types in a right or good answer the computer will 
reply with clapping noises, visual ticks and a 
“Very Good!" message. Moreover the student can 
replay screens if the exercise was not understood. 


The CAL can be stopped at any time and taken 
up again at the students leisure. This is highly 
advantageous to learning, especially in remote 
areas and on community when there are so often 
other things which take priority. CAL offers a 
flexibility in this respect that a travelling co - 
ordinator cannot accommodate - having to come 
and go from that community at a given time. The 
student then has the opportunity to absorb 
information in his/her own time but also therefore 
to realise what is not understood and ask for 
Clarification after that. 


PRESENTATION TECHNIQUES 


One factor important to discussing the success of 
CAL has been the perception that it is an 
impersonal mode of delivery and presentation. 
Some students, indeed most people have an 
Opinion about computers; many having a 
psychological block perceiving them as isolating 
and and unfriendly. This is not a response to CAL 
but the computer. One way of reducing this fear is 
to put students through shorter packages to start 
off with. Another useful technique is to sit the 
whole group together to go through it the first 
time, selecting the most fearless student to 
operate it! Moreover, the ability of CAL to 
respond by name to the person operating it creates 
a more personal learning atmosphere for the 
Student. 


The CAL. package is advantaged by having 
sound and colour. It provides a vibrancy to 
learning that is encouraging. To some extent in 
fact, the packages have also helped to breakdown 
some of the misconceptions about computers. 
One experiment that worked particularly well was 
in using examples, pictures and photographs of 
the rangers themselves which made the CAL. 
exercise more humorous generally and therefore 
the issues absorbed more succinctly. Musical 


Term 3 - 1993 I] 


noises such as the didgeridoo, animal noises (in 
the CAL Mammals) and computer music have 
added to this dimension of CAL and its success. 


CAL. packages promote a creative approach to 
information and presentation. Video, written 
exercises, tables, graphs, interactive diagrams, 
photographs, maps, and audio narrative 
accompanied by words or pictures allows some 
information that is often hard to absorb normally, 
to become more readily conveyed. For example 
one CAL. package was describing the various 
structures of parliament and the constitution - 
information usually classically labelled ‘boring’. 
In this case the package presented the 
information as if in a game show quiz with ¢¥ 
faces of ministers and a whos who? and F, 


whats what? exercise. JB 
The length of the CAL is also e mq 


important. A CAL over forty | tee 
minutes is probably too long. However if if 
is cut up into sections the students feel they can 
finish one section and then move on. 


COURSE CONTENT 


Of course the content of the CAL. package is an 
influencing factor in its success. Some CAL 
packages have been more successful than others 
partly due to its content. For example, even 
though the CAL on parliament is presented in a 
most innovative way the content did not please as 
much as the CAL on Anthropology and 
Archaeology and Australian Plants and Animals. 


The choice of suitable material by the course 
writer concerned is of importance here. It is often 
a matter of taste and inclination that provides the 
variation in course content and approach in CAL. 
The awareness of such course writers to both the 
need of the students and how they perceive they 
should be taught has also caused variation in the 
packages. Some packages are more accessible 
than others. The incorporation of cultural and/or 
community content is another factor. 


CAL AND CULTURE 


The nature of the ranger program is such that the 
cultural context of any given subject is very 
important. The CAL. packages that have been 
most popular have taken note of the cultural/ 


12 Term 3 - 1993 











New South Wale 





community context. The Management CAL. is 
one such example. It is not easy however to 
accommodate this aspect as there are so many 
different communities delivered to and so many 
different cultures. CAL.packages have not so far 
been developed for the Traditional Management 
Courses - CAL. does not have the ability except 
at a very basic level to deal with these issues nor 
is it always appropriate. CAL. such as with the 
Australian Plants and Animals draw their 
examples from the regions or countries of those 
communities; in this instance using pictures of 
plants and animals with which the students were 
iliar and could relate the biological processes 


ng - to. Cultural content and relevance is certainly an 


\ wren that needs close attention in all future 
Wo packages for the course. 


iN NAVIGATION SYSTEMS 


N pe he technical smoothness of CAL is 
ore area that has changed and still needs 

‘fmprovement. The navigation system in 
particular has become increasingly more 
sophisticated since the first packages developed. 
The first packages were particularly hampered in 
making the student redo the whole package up 
until the point at which he/she finished last time. 
This still happens but packages are now cut into 
sections and therefore the student can go to an 
individual section. Nonetheless this detail means 
there is undoubtedly pressure to finish and 
promotes a tendency not to return to the package 
if an interruption occurs. 


Moreover, packages are still a little slow in terms 
of dragging answers, responding to students 
answers and continuing to the next screen. There 
is a lag time and this can prove boring and 
counter the effect of the audio visuals and music. 


Students often cannot simply go back to the next 
screen to examine or look at a diagram - the 
exercises of which they have just completed. If a 
student wishes to re - examine this information 
they must do the entire exercise again. This 
usually means they will not go back. 


Learning ways to improve in this regard is a 
process of trial and error. However as a result, 
CAL navigation systems undergo constant change 
and improvisation, becoming smoother each time 
to operate. 





Information Transfer 


Computer Education Group 


LOADING AND PRINTING CAL 


Crucial to the smooth operation of CAL. 
packages is their loading. This has been a big 
problem in many communities in that often tutors 
or students are not aware of how to load a 
package. If in the process something goes wrong, 
the CAL often will not work. This is not a major 
problem in that it is easily fixed with training. 
However it must be realised that not all 
communities have access to computers, except 
perhaps through their councils, and thus 
familiarity with it is limited, and potential for 
confusion greater. 





One technical aspect that has been particularly 
successful is that there is now an option to print 
every screen. This means that if a student wishes 
to redo keep any particular information it can be 
obtained in hard copy. Printing also opens up 
options for assessment within each subject. 


ASSESSMENT 


With regard to assessment there is a great deal of 
difficulty in defining CAL's role. In the Ranger 
program so far, the CAL. exercise has been used 
as a Supplement to the work in the course or 
workbook, or presenting new information. Some 
questions in the workbook that have been 
assessable have relied on the students preview of 
CAL. For example in the Politics and Change 
workbook an exercise asks; Explain the 
Constitution. How many levels of parliament are 
there? The differing conception of time between 
aboriginal and western peoples formed the basis 
of a different discussion in the Management 
workbook - but also relied on a preview of the 
CAL. on time management. 


The Australian Plants and Animals CAL is 
different in that having the print option has made 
it possible to print out an assessable exercise. One 
example is where the student is asked to explain 
how an oxygen molecule in the atmosphere 
becomes converted to use in the hind leg of a 
running dingo. Having typed the answer in, the 
Student has to print it out and attach to the 
workbook. Or the students are asked to label the 
parts of a flower drawn on the screen and then 
print the diagram out. This has been quite a 
fruitful exercise as students appear much keener 
to answer the CAL in order to get a printout. 





Information Transfer 


It is not possible however to translate all of the 
assessment through CAL as it defeats the purpose 
of it, which is to advocate self paced learning. 
Learning will not be self paced if it is under the 
pressure of a constant assessment scenario. 
Therefore in the ranger program while certainly 
possible to use CAL. as a workbook supplement it 
cannot replace it. 


THE FUTURE OF CAL 


Which brings us to the question - what is CAL's 
future role? CAL. is certainly capable of high 
sophistication in delivery and educational 
learning strategies. However, it is not viable that 
CAL. become the only option for Remote 
delivery education programs. The human element 
is a vital one and the human mind so 
immeasurably more complex than even CAL. that 
it takes a responsive mind to perceive where 
students are having difficulties in comprehending. 
The unique personality of each individual means 
that although CAL. is diverse in approach it 1s not 
diverse in response. It is response that is cructal to 
facilitating educational awareness and thought. 


This is where CAL has another problem - in the 
way it elicits responses. CAL 1s presently 
Structured to ask for certain answers to certain 
questions. If they do not come up the student gets 
a message saying “Try Again’. This promotes the 
idea that there are wrong answers and right 
answers whereas some wrong answers may in fact 
reflect a highly creative and reflective response to 
the question - a fact that can be recognised by a 
teacher, even though the answer shown may 
Strictly speaking be incorrect. Or even, while the 
answer may be wrong it may show incredible 
improvement on behalf of that particular student. 
In this instance CAL. does not have the ability to 
cater to the individual needs of the students or 
anticipate them. 


This approach apart from anything else could 
facilitate that type of education structure that 
examines questions like Two plus two equals ? 
rather than Why does two plus two equal four ” 
This stilts the development of creative thought 
patterns and learning can become narrow tn 
conception. This is where the collaboration 
between course writer and programmer Is crucial 
to ensure there is a mutual understanding of the 
possibilities of CAL. 


Term 3- 1993 13 


-New South Wale 





CONCLUSION 


CAL. then for all its advantages is best used as an accessory ‘nd supplement to delivery, even in remote | 
areas. The teleconference still has a more personal touch, as do co-ordinators or tutors. CAL. is however 
invaluable in maintaining student interest and humour, with the printing option p:oviding ways of obtaining 
graphic iriformation immediately. CAL also is, without question providing some of the most innovative 
advances in education and delivery strategies, and its future potential and directions can be looked forward 

' to. | 


ACKNOWLEDGEMENTS 


Gotts, A (1993). Using Quicktime to Teach Literacy: Instructional Design ideas for low cost users. Cairns 
College Of TAFE. | 


Gotts, A. Kruger,L.Colmer,D. Makray, J. and Hill, R. (1992) The Remote Area Teacher education Project 
(RATEP): An initiative in Interactive Multimedia Technology. Cairns College of TAFE. 


- JUNE (1993).'Discussions with Rigsstiaty Hill, Alison Gotts, members of the Computer Programming 
Team for Ranger and RATEP, and Co - ordinators from the Ranger Training Program. 


Shane Wharton 
Dip. Teach. ,B.Ed., 

_ Grad.Dip.Edu.Studies(Comp Ed) 
Northern Regional Manager 





NEW HORIZONS 


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Parramatta, N.S.W. 2150 G RAEME A INSWORTH 
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14 Term 3 - 1993 Information Transfer 


Computer Education Group 





Apple: dedicated i a Youre already a trained teacher. 


to learni ng. 


»  9Owhy spend months leaming a computer 
Ret system? With an Apple Macintosh, you won't 
“is | — have to. We designed it with productive 
| professionals in mind. 

ee Our computers are so easy to use, you can 
# } start work straight away using the Macintosh 
| for what you do best - your job. 

Your Macintosh will make lesson 
preparation easy and enjoyable. And you'll be 
saving time with the many teacher productivity 
programs available - programs that let you 
produce standard program formats each term, 
maintain reports on your students and weight 
and scale marks automatically. 

Suddenly, preparing the school newsletter, 
notices and take-home notes for parents is half 
| | the chore it used to be. The Macintosh has 
a , many simple publishing programs to make 

a aie your work easier and the end results will look 
great. 
—_ . Storing work on the computer disk means 
~ ae that next time you need a similar hand-out, it's 
just a matter of altering dates and venues, 
without reworking the whole concept. With 
your Macintosh youll find regular work takes 


a few minutes to re-do instead of hours to do 
() () over again, giving you more time with your 
, family and friends. 


So if you're the kind of teacher who loves 


; ¥ teaching, but doesn’t want to know about 
fe dC ] IY 1S computing, the friendly Macintosh is the 


computer you've been looking for. 


For more information, contact Chris at 008 


second nature 025 355 for the location of your nearest Apple 
8 


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Computing probably isn’t) 9 
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Information Transfer Term 3- 1993 15 





New South Wal 





Just about every clip art collection in 
existence has a selection of "International 
Signs", but often these signs are without 
any explanation of their meaning. 


As we in Australia lead sheltered lives, 
here are some of the international signs 
and their meanings: 


Information Flow 
Point 





Virus Protection 
Installed 





User Group Meets 
System Reset In Here 
Process | Wait Here For | 
Printer To 
sh Technician 
Available 
Immediately 





a rT AY Sr 





Old Software se a 
Prohibited Be Thrown 
From This Point : H 
Newton : : 
Powerpoint bh. og Of 
! Ahead Computer Co-ordinato 
\ | Next 96km 





Attempting To Carry © 





This Computer Will 
Break Your Legs 
| Help Is Just A | 
— Call ive Left Your Report 
way Printing Over There. . . 
Plugging Leads Into 
Left End of CPU 


Could Cause Fires 





16 Term 3 - 1993 Information Transfer 


Computer Education Group 





Can You Write Me Some Tools That... * 


Clive Lynn 
*Reprinted from the LOGO '93 conference proceedings 


Some time ago a fellow staff member asked me if 
I would write a set of tools on number theory that 
he could use in his VCE classes, tools that would: 


a) generate Fibonacci numbers, 
b) test a number for primality, 

c) generate the prime factors of a 
number d) solve pairs of linear 
simultaneous equations 


The following paper is a ‘walkthrough’ of the 
process I followed in producing them, together 
with some thoughts that may be of interest to 
teachers. 


Before finally starting I went back to the person 
requesting the tools and after further discussions 
the range was extended to the following modules: 


1 Fibonacci Numbers 

2 Divisors (Factors) 

3 Greatest Common Divisor 

4 Lowest Common Multiple 

5 Prime Numbers 

6 Prime Factors 

7 Linear Simultaneous 
Equations 

8 a Menu 


I always begin a project like this one by 
consulting the literature as widely as I can and 
collecting ideas that I think will be useful, and as 
this is done for my own purposes I'm often 
careless about noting the source of the ideas. 


T his paper is a reconstruction of that process and 
whilst I believe that I've referenced all my 
sources, it is likely that some have been 
missed...mea culpa... 


The code that goes with each module is at the end 
of the paper and is heavily internally documented. 


Information Transfer 


Modulel: FibonacciNumbers 

The purpose of this tool is to be able to generate 
the requested number of members of the series 
known as the Fibonacci Series. 

This series of numbers, which begins: 


0112358 1321 34 


can be defined as: 
0 ifn=O 


Fib (n-1 ) + Fib (n-2)otherwise 


My first attempt at writing a procedure to 
generate this series was based directly upon the 
series Of values listed above, rather than the 
formal definition of the series. I felt that it was sc 
very Similar to generating factorials using a onc 
line recursive procedure that it would be easy to 
use this as a model. Put simply, I failed and was 
forced to find and use a formal definition of the 
series (e.g. Abelson & Sussman, 1986, p 35) te 
work from. The source that I used contained i 
procedure, written in Scheme, that I converted te 
Logo. It worked fine, except that it was so very. 
very slow that it would have driven the students 
crackers waiting for the numbers to appear! - 
requesting 10 values took 3 seconds. asking fo: 
15 values required 26 seconds. 20 values took 
five minutes! 





Timing was done ona Mac Plus with 2.3. es of RAM 
using LogoWriter 


ee cme = ite 


term3- 1993 17 





[8 Term 3 - 1993 


The solution, again found in Abelson & Sussman 
(page 36), made use of what they describe an 
iterative process and in this case the first 20 
values appeared in’5 seconds. The trade-off is that 
this second, more efficient method, has code that 
is more difficult for the student to follow, as the 
following comparison shows: 


Simple Recursive Method: 
To Fib : number 
IF : number = O [OP 0 ] 
IF :number = 1 [OP 1] 
OP (Fib : number A 2 ) + (Fib : 
number-I1 ) | 
END 


Iterative Method: 
To Fib2 : a:b: count 
IF (:count = 0) [STOP] 
INSERT : a TAB 
Fib2 :b (:a + :b) (:count A 1) 
END 


This pattern of trading speed for complexity of 
logic was one that was to appear regularly 
throughout the development of these tools. 


One unintended outcome of this module is that 
after the 48h term, the numerical output changes 
from integer representation to real number 
representation. This provoked several worthwhile 
discussions with students concerning the _ 
representation of numbers within the computer 
and the loss of accuracy (and thus of information) 
that results. 


Module2:GreatestCommonDivrisor __ 
Methods for determining the Greatest Common 
Divisor (gcd) either by hand or using a computer 
are readily available; many make use of the 
Euclidean Algorithm. See (Courant & Robbins, 
1941, p 44) and (Graham, Knuth & Patashnik, 
1991, plO3), for a description of the algorithm 
itself; (Dromey, 1982, p97) and (Rohl, 1984, p4) 
provide typical implementations using Pascal 
whilst (Abelson & Sussman, 1985, p44) provides 
an implementation written in Scheme. 


As my starting point I used the description 
provided by Graham et.al. (p. 103) which states 
that: 

gcd (n,m) = gcd (m mod n, n) 


New South Wale 


Working through the algorithm showed exactly 
how it works and allowed me to develop a mental 
picture of the process, something that I need to 
have before I generate the code. 


eg. gcd (18,30) = gcd (12,18) 
gcd (12,18) = gcd (6,12) 
gcd (6,12) = gcd (0,6) 
since the last iteration produced zero as the 
remainder, the gcd (18,30) is 6.2 


This can be implemented directly in Logo as: 


To gcd : numl ; num2 

IF :numl=O[ OP: num2 ] 
ecd (REMAINDER : num2 : numl ) : numl 
END 


a function that uses tail recursion to find the gcd 
of the two input values. (For the Pascalians 
amongst you, the Logo primitive REMAINDER 
is equivalent to Pascal's MOD ) 


As an aside it was instructive to compare the 
complexity of Dromey's analysis (some eight 
pages), with the simplicity of say Rohl's (at about 
eight lines) as something to be wary of when 
searching the literature for an appropriate 
algorithm. This became important later when 
considering prime number generation and prime 
factors - see modules 4 to 6 later. 


Module3:LeastCommonMultiple 

When reading Graham et. al. for ideas on 
determining the gcd of two integers, they referred 
on page 103 to exercise 2 on page 144. 


Its solution provided a simple algorithm for 
determining the Least Common Multiple (Icm) of 
two integers: 

gcd (m,n) x lem (m,n) =m xn 


which gives, after rearranging: 


Icm (m,n) = m x n/ gcd (m,n) 


As the previous module had involved developing 
a procedure to determine the gcd of two integers, 


2 This result can be verified easily by listing all the factors 


(divisors) of both 18 and 30 and selecting thc largest value 
that is common to both. This is the process that students are 
introduced to, but for VCE students I felt that Euclid’s 
Algorithm was more appropriate, as well as more efficient. 





Information Transfer 


Computer Education Group 


the procedures for determining the Icm of two 
integers became obvious: 


TO Icm :numl :num2 
OP (:numl * snum2)/ (gcd :numl :num2) 
END 


together with 


TO gcd :numl :num2 

IF :numl = O [OP :num2] 

OP qcd (REMAINDER :num2 :numl) :numl 
END 


A good example of serendipitous outcomes that 
sometimes occur from literature surveys 
particularly helpful for a relative non- 
mathematician like myself. 


Modules 4, 5 tr 6: Factors, Prime Numbers 
and Prime Factors 

I’ve decided to comment on these three modules 
together because their development became so 
intertwined. 


I started by looking at the task of generating 
prime numbers and although I was vaguely aware 
that I was heading into some heavy computing 
and that I would need to brush-up my 
understanding of number theory, I really didn't 
expect it to be so difficult to generate prime 
numbers up to say 10,000. A number that seemed 
to me to be rather small as numbers go! 


As always, I started off by developing a mental 
picture of what I was trying to do and to this end I 
readily found information on prime numbers 
(Courant & Robbins, p. 21) and on the Sieve of 
Eratosthenes (ibid. p. 25); algorithms coded in 
Pascal (Dromey, 1982, p. 105) were found and, in 
a recently purchased text by Cuoco (Cuoco, 1990, 
Ch 10), a series of procedures in Logo. These 
procedures made use of the Filter procedure 
(Harvey, 1985, p. 217) and gave me a way of 
avoiding the use of arrays and using lists as an 
input stream to then filter out factors and so leave 
only non-factors (primes) in the list. 


Almost immediately problems began to appear. 
Whilst the method described in Cuoco worked, it 
resulted in the error message ‘Out of stack space’ 


Information Transfer 


for numbers very much smaller (maximum of 538 
on a 2.5 Mbyte RAM Macintosh) than I was 
aiming for. The initial culprit was a procedure 
(function) called List . Upto (CUOCO, p. 276): 


To List. Upto :num 
[F :num = 1 [OP []] 
OP SE (List.Upto :num-1) :num 
END 


A quick examination showed that all invocations 
remain ‘alive’ until: num = 1 is reached, so I 
replaced it with Make . List, which is rather less 
elegant but produced larger lists and had the 
added advantage of being much faster: 


TO Make.List :value ‘newllst 

IF :value = 1 [OP []] 

MAKE “newlist FPUT :value :newlist 
OP MakeList :value - 1 :newlist 

END 


Make. List will handle values in excess of 10,000, 
modifying it to exclude even numbers greater 
than '2' would double this. 


Having made this change I was somewhat 
disappointed to find the same error message for 
values greater than 800; this time in the procedure 
called Not _ a_ Factor?. Closer examination 
revealed that the real problem lay not with Not _ 
a_ Factor? itself, but with the combination of 
procedures used to implement the sieve. All of the 
central procedures use embedded recursion, each 
taking up stack space until the limit is reached. 
The only solution was to find an alternative way 
of generating prime numbers. Did a faster test 
exist that I could use in a similar manner’? 


An examination of the literature soon showed that 
a vast array of prime number generators existed 
ABelson & Sussman, p. 45],{Knuth, 1981, pp], 
[Cormen, Leiserson & Rivest, 1991, p.837] and 
[Ribenboim, 1991], finding one that I could 
decipher, let alone one that the students could 
understand, proved more difficult. The modern, 
(supposedly faster) algorithms use probabilistic 
methods to achieve their results, and whilst the 
Miller-Rabin test [Cormen et al, p. 840] is 
described as fast, I decided to use a test due to 
Wilson [Crandall & Colgrove, 1986, p. 46] which 
was much easier to understand and code. It turned 
Out to be slower than the current method. 


Term 3 - 1993 








19 





20 Term 3 - 1993 


Wilson's Theorem itself says that D is a prime 
number if 
(p - 1)! ae =p-l 


This can be written as a pair of Logo procedures: 


TO Wilson? :num 

MAKE "factorial 1 | 

IF ((Wilson2 :num -factorial 1) + 1) = :num 
[OP "true] 

OP "False . » 3 

END 


TO Wilson2 :num :factorial :count 

IF :count = :num [OP -factorial] 

MAKE ~‘factorial (REMAINDER (:count * : 
factorial) :num) 

OP Wilson2 :num factorial (:count + 1) 

END | 


which in turn can be incorporated into the 
primelIst procedure to give: 


TO PrimeListW -list 
, [this takes a list as input and deletes all non- 
| _ prime members] 
IF EMPTYP :list [OP []] 
IF (wilson? (FIRST :list)) [OP FPUT (FIRST 
‘list) PrimeListW BF -list] 
OP PrimeListW BF :list 
END 


Unfortunately this method is significantly slower 
than the method in the code provided. In Object 
Logo it will provide output to input numbers in 
excess of 5000, prover’ you are prepared to 
wait! 


The code listed (based heavily on Cuoco) makes 
use of the original procedures and the first screen 
warns the user that the maximum value is 800. 


Module7:LinearSimultaneousEquations 

One of the simplest algorithm that can be used to 
solve linear simultaneous equations in two 
unknowns makes use of matrices and Kramer's 
Rule. It is also a method that the students will 
have used in their mathematics classes. 


For two equations, say: 


ax+by=kl1 
cx + dy = k2 


New South Wale 


in matrix form look like: - 


ie 

Cc 

{ab 
Pa] 

The coded solution is little more than the 

conversion of the above into Logo and in the form | 

presented is a nightmare of FIRST and BF's, 

LAST and BL's. It does however, have the 


advantage of being very simple to follow at the 
level of its logic if not of its code. 


To SimultSolv :coeffs :outlist 
MAKE "x Determinant (LAST FIRST :coeffs) 
(LAST LAST :coeffs) (FIRST BF FIRST :coeffs) 
(FIRST BF LAST :coeffs) 
MAKE "y Determinant (FIRST FIRST :coeffs) 
(FIRST LAST :coeffs) (LAST FIRST 
:coeffs) (LAST LAST :-coeffs) 
MAKE "det Determinant (FIRST FIRST :coeffs) 
(FIRST LAST :coeffs) (FIRST BF FIRST 
:coeffs) (FIRST BF LAST :coeffs) 
MAKE "“outlist LIST (: x/ :det) (:y/ :det) 
OP :outlist 
END 


TO Determinant :RICI :RIC2 :R2C1 :R2C2 
OP (:RIC1 * :-R2C2) - (:R2C1 * :RIC2) 
END 


Module8:Menu 

The tools presented here have been field tested by 
a year 7 mathematics class and all the modules 
work quite well except for a ‘fault’ present in all 
of them. When prompted for an input, be it a 
single number or a yes/no, the modules do not 
check adequately for a legitimate response, 
instead they accept what they are given and then 
‘crash’ when it is the wrong type. This would need 
to be remedied if you wanted to usc it regularly in 
a Class. 





Information Transfer 


Computer Education Group 


This problem can be easily overcome by use of 
some error trapping routines that check to see if 
the response is appropriate and beeping or 
whatever if it is not. These programming 
requirements are not peculiar to Logo but 
common to all languages. 


Codel:FibonacciNumbers 


TO ; :comment 
END 


TO Fibonacci 

CT HT 

PR [This program prints out as many Fibonacci 
numbers as you request.] 

PR [To use it, press the <RETURN> key and 
enter the number of terms required. It assumes 
that ZERO is the first term] 

Pause 

Fib 

END 


TO Pause 

, [cause execution to stop until a key is pressed] 
IF NOT EMPTY? READCHAR [STOP] 

Pause 

END 


TO Fib 

, [the ‘main’ program, prompts for how many] 
; [and then calls Fib2 to generate them] 
CT 

BLines 3 

(INSERT [How many terms? :] Blank) 

MAKE "number FIRST READLIST 

BLines 2 

IF :number = O [PR 0 STOP] 

Fib2 0 1 :number 

PR Blank Blines 2 

Repéat? [Generate more? (Y/N)] 

END 


To Fib2 :a :b :count 

, [outputs the fibonacci numbers, :count is a 
decrementing counter] 

IF (:count = 0) [STOP] 

INSERT :a TAB 

Fib2 :b (:a + :b) (:count A 1) 

END 


TO BLines :num 

; [prints :num blank lines] 
REPEAT :num [PR []] 
END 


TO Blank 

, [prints a blank character] 
OP CHAR 32 

END 


Information Transfer 





TO Repeat? :message 

; [prompts to see if further fibonacci numbers 
are wanted] 

Blines | TAB 

INSERT :message 

MAKE "ans FIRST READLIST 

IFELSE OR (:ans = "Y)(cans = "y) [CT 

Fib] [Finish] 

END 


TO Finish 

CT | 

BLines 9 TAB TAB PR [Goodbye.] 
WAIT 30 | 

CT CLEARNAMES 

GETPAGE "Menu 

END 


Code2:GreatestCommonDivisor 


TO ; :comment 
END | 


TO BLines :num 
REPEAT :num [PR []] 
END 


TO GCDivisor 

CT CG HT 

PR [This program determines the Greatest] 
PR [Common Divisor (GCD) of two integers.] 
GCD Input 

END 


TO GCD Input 

BLines 2 

INSERT [Enter the two numbers whose GCD 
you wish to find: ] 

MAKE "Numbers READLIST 

MAKE "A FIRST :Numbers 

MAKE "B LAST :Numbers 

BLines 2 ; 

(INSERT [The GCD of] blank :A blank [&] 
blank :B blank [is:] blank) 

PR GCDiv :A :B 

BLines 2 

Repeat? [Solve another? (Y/N)] 

END 


TO GCDiv :numl :num2 
; [determines the greatest common divisor of 


_inuml and :num2] 


[IF :numl = O [OP :num2] | 

OP GCDiv (REMAINDER :num2 :numl) :numl 

, if inuml > :num2 then the first time through 
they simply get] | 7 

[ reversed, hence input order does not matter] 
END 7 





Term 3 - 1993 


Term 3 - 1993 


TO Repeat? :message 
, [prints request for more, if not then ‘Finish’] 

INSERT | ‘message | 

MAKE "ans FIRST READLIST 

_IFELSE OR (:ans = "Y)(cans = "y) [CT 
GCD.Anput] [Finish] 

, [anything other than ‘y’ or 'Y’ results in 
Finish’] 7 

END 


TO Finish 

; [cleans up and returns to the main menu] 
CT BLines 9 TAB TAB 

PR [Goodbye.] 

WAIT 30 

CT CLEARNAMES 

GETPAGE "MENU 

END 


TO Blank 

; [prints a blank character] 
OP Char 32 

END 


Code3:LeastCommonMultiple 


TO ; :comment 
END 


TO Blank 
OP CHAR 32 
END 


TO BLines :num 
REPEAT :num [PR []] 
END 


TO LowComMult 

CT HT 

PR [This tool determines the LCM of two 
integers. ] | 

PR [It makes use of the fact that the LCM of 
two numbers A & B is given by] 

PR [A x B! GCD(A,B).] LCM Input 

END 


TO LCM Input 

PR[]PR{] — 
(INSERT [Enter the two numbers whose LCM is 
to be determined:] Blank) 

MAKE "numbers READLIST 

MAKE "numl FIRST :numbers 

MAKE "num2 LAST :numbers . 

PR [] 

(INSERT [The LCM of] :numl [&] :num2 [is:] 
blank ) 

PR LCMult :numl :num2 

PR [] 

Repeat? [Solve again? (Y/N):] 

END — | 


New South Wales 


TO LCMult :numl :num2 
OP (:numl * :num2)/(GCDiv :numl :num2) 
END 


TO GCDivv :numl :num2 
IF :numl = O [OP :num2] 





OP GCDiv (REMAINDER :num2 :numl) :numl 


END 


TO Repeat? :message 

INSERT :message 

MAKE "ans FIRST READLIST 

IFELSE OR (:ans = "Y)(:ans = "y) 
LCM Input] [Finish] 

END a 


TO Finish 

CT 
BLines 9 © 

TAB TAB 

PR [Goodbye.] 
WAIT 30 . 

CT CLEARNAMES 
GETPAGE "MENU 
END 


Code4:Divisors(Factors) 


TO Divis? : num ; denom 

> [returns True’ if num/denom = integer] 
OP (REMAINDER : num : denom) = O 
END 


TO MakeList :value :outlist 

IF :value = O [OP :outlist] 

MAKE “outlist FPUT :value :outlist 
OP MakeList :value A 1 :outlist 
END | 


TO Apply :function :value 
; [used in the procedure Filter] 
; [combines a function and a value and 
RUNS it] 
OP RUN SE -function Suite 
END 


TO Divisors.Calc :number 


[CT 


then 


; [applies a division ‘filter’ to the list of 


integers up to :number] 


[i.e. outputs those numbers in wile list that 


alile into :number] 


OP Filter "Divis? :number (MakeList :number 


{}) 
END 


Information Transfer 





ymputer Education Group 





— Filter :pred :value :inlist 
: [returns a list of value that have been filtered 
according to] 
; [the predicate test that has been applied to each 
sales in cinlist] 
; [the empty list becomes the ‘first’ member of the 
list of divisors] 
_ IF EMPTY? :inlist [OP[]] 
_ IF (Apply :pred SE :value (FIRST :inlist)) 
[OP FPUT (FIRST :inlist) (Filter :pred :value 
_ (BF :inlist))] 
| OP Filter :pred :value (BF :inlist) 
END | 


TO SumList vinlist 

IF empty? -inlist [OP 0] 

OP (FIRST :inlist) + SumList BF -inlist 
END 


TO Divisors 

CT HT 

PR [This tool determines the divisors] 

. PR [of a number and their sum and prints them 

* out.] | 
Divisors Input 
END 


TO Divisors.Input 

BLines 2 

(INSERT [Enter the number whose divisors are to be 
found:] Blank) 

MAKE "number FIRST READLIST 

BLines 1 

(PR [The divisors of] number [are:]) 

Blines 1 

MAKE "“divlist Divisors. Cale : ‘number pr :divlist 

BLines 1 

(PR [and their sum is:] sumlist :divlist) 

Repeat? [Solve another? (YIN)] 

END 


TO Blank 
OP CHAR 32 
END 


TO BLines :num— 
REPEAT :num [PR []] 
END 


TO Repeat? :message 

Blines 1 

TAB INSERT :message 

MAKE "ans FIRST READLIST — 

IFELSE OR (:ans = "Y)(cans = “y) [CT 
Divisors Input] [Finish] | | 

END 


TO Finish 
CT BLines 9 
TAB TAB PR [Goodbye.] 


WAIT 30 


CT CLEARNAMES | 
GETPAGE "MENU 
END | 


Code5:PrimeNumbers 


TO ; :comment 
END 


TO PrimeNumbers 
CT HT 
PR [This program determines and prints out the 


prime numbers up to the value entered. The maximum 
value is 800] 


Prime.Calc 
END : 


TO Prime.Calc 

INSERT [Enter the upper limit:] 

MAKE "value FIRST READLIST 

CT (PR [The prime numbers less than] :value [are: i ) 
BLines 1 

Display Prime_Upto_E :-value 

P tid 

Repeat? [Print to a new maximum? (Y/N)] 

END 


TO Display :inlist : 
; [prints out a list of values as a simple table]. 
IF EMPTY? :inlist [STOP] 

(INSERT FIRST :inlist” ) 

Display BF -inlist 


_ END 


TO Prime? :number 
, [tests to see if :number is a prime number] 
IF - ‘number = 2 [OP "True] 
IF Even? :number [OP Easels [if its even then not 


prime] 


OP PrimeHelper :number 3 ; [first divisor is 3 - odd 


numbers only] 


END 


TO PrimeHelper :num :divisor 

IF (:divisor > sqrt :num) [OP "True] 
; [no need to check beyond ~num] 
IF Divis? :num :divisor [OP "False] 
OP PrimeHelper :num (:divisor + 2) 
END 


TO Divis? :numerator :denominator 

: [returns ‘True’ if] 
OP (REMAINDER -:numerator :denominator) = 
END 


Information Transfer 


Term 3 - 1993 23 


24 Term 3 - 1993 


TO Even? :num 
OP Divis? :num 2 
END 


TO PrimeList :list 

, [a prime number filter that works by testing each 
member of the] 

, [listfor primality it results in a list of primes] 

IF EMPTY? :list [OP []] 

IF Prime? (FIRST :list) [OP FPUT (FIRST: list) 
PrimeList BF -list] 

OP PrimeList BF :list 

END 


TO MakeList :value :newlist 
» [clumsy, but in tail recursive form to handle larger 

bere 

‘f] 

IF :value = 1 [OP :newlist] 

MAKE "“newlist FPUT :value :newlist 

OP MakeList :value - 1 :newlist 

END 


TO Not_A Factor? 3 :n 
OP NOT Divis? :n f 
END 


TO Eratosthenes :inlist :outlist 
[this works by progressively removing (sieving) all 
of the ] | 
[multiples of values < the SQRT of the largest from 
inlst] 
[This leaves two lists of primes, one the values 
smaller than ] 
‘[SQRT of largest and another of the larger values ] 
;[ -they are then combined as the final step] 
if] 
IF (FIRST :inlist) > SORT (LAST :inlist) [OP 
SE :outlist :inlist] 
OP Eratosthenes (SIEVE "Not_A_Factor? (FIRST 
tinlist) BF :inlist) (LPUT FIRST :inlist :outlist) 
END 


TO Primes_Upto_E :number | 

; [the Eratosthenes sieve version] — 

OP Eratosthenes MakeList :number [] [] 
END 


TO Sieve :pred :value -inlist 
, [see comments in Eratosthenes above] 
IF EMPTY? :inlist [OP []] 
IF Apply :pred (SE :value FIRST . inlist) [OP FPUT 
FIRST :inlist (Sieve :pred :value BF -inlist)] 
OP Sieve :Dred :value BF :inlist 
END 


TO Apply function :value_ 

, [this 

OP RUN SE -function :value 
END 


Information Transfer 


New South Wai 





TO Repeat? :message 
Blines 1 
_ INSERT :message 
MAKE "ans FIRST READLIST 
IFELSE OR (:ans = "Y)(:ans = "y) [CT 


Prime.Calc] [Finish] 


END 


TO Finish 

CT 

BLines 9 | 

TAB TAB 

PR [Goodbye.] 
WAIT 30 

CT CLEARNAMES 
GETPAGE "MENU 
END 


TO BLines :num 
REPEAT :num [PR []] 
END 


Code6:PrimeFactors 


TO ; :comment end 


TO PrimeF actors 
CT 
PR [This program determines the prime factors of 
a number and prints] 
PR [them out] 
PR [lt works for numbers up to at least 100000 


but can be slow!] 


PrimeFactors Input 
END 


TO PrimeFactors dnput 

BLines 2 

INSERT [What number do you wish to find the 
prime factors of?] 

REPEAT 2 {INSERT Blank] 

MAKE "number FIRST READLIST 

BLines 2 | | | 

(PR [The prime factors of] :number [are:]) 

BLines 1 | 

TAB 

Factors :number [] 

Repeat? [Solve another? (Y/N)] 

END 


To Prime? :number 

; [tests to see if number is prime A slow!] 

IF :number = 2 [OP "True] 

IF Even? :number [OP gels uf its even its 
not prime] . 

OP PrimeHelper :number 3 

END 





Computer Education Group 


To PrimeHelper :number :odd_integer 
; [reduces the numbers to be led by excluding all even 
numbers>2] ] 
IF (:odd integer > SORT : sapbies ) [OP "True] — 
; [no need to check beyond sqrt :num] 
IF Divis? :number :odd_integer [OP "False] 
OP PrimeHelper :number (:odd_integer + 2) 
END | | 


TO Divis? :numerator :denominator 

; [returns True’ if num/denom = integer] 

OP (REMAINDER :numerator :denominator) = O 
END 


TO Even? :num : 
OP Divis? :num 2 ; [op's "true" if :num is even] 
END 


TO MakeList :value :newlist 

; [inelegant but memory efficient list maker] 
IF :value = 1 [OP :newlist] 

MAKE "“newlist FPUT -value :newlist 

OP MakeList :value A 1 :newlist 

END 


TO Not_A Factor? -f :n 
OP NOT Divis? :n f 
END 


TO Eratosthenes :inlist :outlist | 
IF (FIRST :inlist) > sqrt (LAST :inlist) [OP SE :outlist 
‘inlist] 
OP Eratosthenes (SIEVE "Not_A_Factor? (FIRST :inlist) 
BF :inlist) (LPUT FIRST -inlist :outlist) 
END 


TO Primes_Upto_E :number 
OP Eratosthenes MakeList :number [] [] 
END 


TO Sieve :pred :value :inlist 

IF EMPTY? :inlist [OP []] 

IF Apply :pred (SE :value FIRST :inlist) 

[OP FPUT FIRST :inlist (Sieve :pred :value BF 

sinlist)l | 
OP Sieve :pred :value BF :inlist 
END 


TO Apply :function :value 
OP RUN SE -function :value 
END 


Information Transfer 





TO Factor_List :number :prime_list 
: [determines which of the numbers in the list of 


_ primes] 


; [is a factor of :number] 
IF EMPTY? -prime_list [OP []] 
IFELSE Divis? :number FIRST :prime_list 
[OP FPUT (SE FIRST :prime list Ord FIRST 


cprime list :number) 


Factor_List :number BF :prime_list] 
[OP Factor_List :number BF :prime_list] 
_END _ 


TO Ord :prime_no :number 
; [this op's the no of times that :prime no divides into 
ber 
IF NOT Divis? :number :prime_no [OP 0] 
OP 1 + Ord -:prime_no (:number | :prime_no) 
END | | 


TO Factors :number :PList 
; [this prints the prime factors of a number] 
IF Prime? :number [PR (SE ‘number [is a prime 
number]) STOP] 
, [checks to see if the number is prime] 
MAKE "PList (Factor List :number Primes Upto E INT 
SQRT :number) 
‘f] 
IFELSE ((Factor_Check :PList) = :number) 
[Display :PList STOP] 
[Display LPUT (SE (:number / Factor Check :PList) 1) 
-PList] 
END 


TO Factor_Check :Factor_List 
; [this multiplies out and sums the sets of factors in _ 
:-Factor_List] 
IF EMPTY? :Factor List [OP 1] 
OP (Mult Out FIRST :Factor_List) * Factor_Check 
BF :Factor_List 
END 


TO Mult_Out -input 
; [takes a list of two numbers and outputs the first 
raised to the second] 
OP PowerM FIRST :input LAST | ‘input 
END 


TO PowerM :base :index 

; [op’s :base raised to :index] 

IF -index = O [OP 1] 

OP :base * PowerM :base (:index A 1) 
END 


TO Display :PList 
; [displays the list of factors] 
IF EMPTY? :PList [CB DELETE PR " STOP] 
REPEAT LAST FIRST :PList{INSERT FIRST FIRST 
:PList INSERT CHAR 46] 
Display BF :PList 
END 





Term 3 - 1993 2 


New South Wale 





To Blank To SimultSolv :coeffs :outlist 
OP CHAR 32 ; [uses FIRST, BF, LAST & BL to extract relevant 
END values from the lists] 
; [really only a ‘trial’ solution that needs to be tidied 
TO BLines :num up and made] 
REPEAT :num [PR []] , [much more modular instead of having all the 
END MAKE's] 3 
MAKE "x Determinant LAST FIRST -:coeffs LAST 
TO Repeat? :message LAST -coeffs FIRST BF FIRST 
Blines 1 :coeffs FIRST BF LAST :coeffs 
TAB INSERT :message MAKE "y Determinant FIRST FIRST :coeffs FIRST 
MAKE "ans FIRST READLIST LAST :coeffs LAST FIRST 
IFELSE OR (: ans = "YI (~n.~; = "vil r~ :coeffs LAST LAST :coeffs 
END MAKE "det Determinant FIRST FIRST :coeffs FIRST 
LAST :coeffs FIRST BF 
TO Finish FIRST :coeffs FIRST BF LAST :coeffs 
CT MAKE "outlist LIST (:x 1! :det)(:y/ :det) 
BLines 9 OP :outlist 
TAB TAB PR [Goodbye.] END 
WAIT 30 
CT CLEARNAMES 
GETPAGE "MENU TO Determinant :RIC1 :RIC2 :R2CI :R2C2 
END , [evaluates a2 x 2 determinant] 
OP (:RICI * :R2C2) A(:R2C1 * :RIC2) 
Code7:LineatSimultaneousEquations END 


To ; :comment 
END TO Repeat? :message 


BLine 1 TAB INSERT :message 
MAKE "ans FIRST READLIST 


TO SimEqu 
Simul tEqu {] IFELSE OR (:ans = "Y) (:ans = "y) [CT 
END | eee 


TO SimultEqu :outlist 
CT HT | 
PR [This tool will find the solution to a pair of FO BLine :num 
linear simultaneous equations.] REPEAT :num [PR []] 
PR [of the form aX + bY = K] BLine 1 END 
PR [When asked to enter the coefficients, they 
must be entered in the following order:] 


PR [ <x-coeff> <y-coeff> and <constant>] TO Finish 
PR [ for each equation.] CT 
BLine 1 BLine 9 
PR [Enter coefficients for first equation:] TAB TAB PR [Goodbye.] 
MAKE "XYK1 READLIST WAIT 30 
PR [Enter coefficients for next equation:] CT Cay il ES 
MAKE "XYK2 READLIST MAKE "coeffs LIST GETPAGE "MENU 
“XYKI :XYK2 END 
CT 
PR [Your equations are:] TAB (INSERT FIRST | 
FIRST :coeffs "x "+ FIRST BF FIRST -coeffs "y Code 8: Menu 
"= LAST FIRST -coeffs) 
PR" TAB (INSERT FIRST LAST :coeffs "x "+ TO STARTUP 
FIRST BF LAST -coeffs "y "= LAST LAST :coeffs) CT CC CG HT 
BLine 2 NumberStuff 
PR [The solutions are:] MAKE "Ans SimultSolv END 
-coeffs [] TAB TAB (INSERT [x =] Char 32) 
PR FIRST :Ans TAB TAB (INSERT [y =] Char 
32) To ; :message 
PR LAST :Ans Repeat? [Solve another? (Y/N)] END 


END 
3. See Lewis Ch 4 for more information 


26 Term 3 - 1993 Information Transfer 


-omputer Education Group 
TO NumberStuff 
; [this is the main menu that controls access to] 
vee of the ‘tools’] 
[it uses Meee IF’s rather than a custom 
written] 
> [case statement simply to make it easier for 
students to read] 
rE 
HT CT 
BLine 1 
PR 
: Oe ae ee ce aren Nero eee 
INSERT [*]Blanks 28 INSERT [Number Theory 
Menu] Blanks 29 PR [*] 
PR | 
[EEE E EEE TESS TERE ERAT TAC LS ee Te eee 
BLine 1 
_ TAB PR [1 -Fibonacci Numbers] 
TAB PR [2 - Prime Numbers] 
TAB PR [3 - Prime Factors] 
TAB PR [4 - Divisors] 
TAB PR [5 -Greatest Common Divisor] 
TAB PR [6 - Least Common Multiple] 
TAB PR [7 - Simultaneous Equations] 
BLine 1 
TAB PR [9 QUIT] 
BLine | 
TAB INSERT [Select by typing a number: ] 
MAKE "select FIRST READLIST 
Selection :select 
END | 
TO Selection :select 
; [this procedure calls the relevant page and 
runs it] | 
:[] 
IF -select = 1 [CT CC Fibonacci] 
IF :select = 2 [CT CC PrimeNumbers] 
IF :select = 3 [CT CC PrimeFactors] 


IF :select = 4 [CT CC Divisors] 


IF :select=5 [CT CC GCD] 

IF :select = 6 [CT CC LCM] 

IF -select = 7 [CT CC SimultEquations] 
IF :select = 9 [CT CC QUIT] 

CT 

BLine 10 

PR [Numbers between I & 9 only please! ] 
NUMBERSTUFF 

END 


Information Transfer 





TO Fibonacci 

GETPAGE "FIBONACCI 
RUN "Fibonacci 

END 


TO PrimeNumbers 
GETPAGE "PRIMENUMBERS 
RUN "PrimeNumbers 

END 


TO PrimeFactors 

GETPAGE "PRIMEFACTORS 
RUN "PrimeFactors 
END 


TO Divisors 
GETPAGE "DIVISORS 
RUN "Divisors 

END . 


TO GCD 

GETPAGE "GCDI VISOR 
RUN "GCDivisor 

END 


TO LCM 

GETPAGE "LCMULTIPLE 
RUN "LowComMult 

END 


TO SimultEquations 
GETPAGE "SIMULTEQUS 
RUN "SimEqu 

END 


TO Blanks :n 

; [prints multiple spaces] 
REPEAT :n [INSERT Blank] 
END 


TO Blank 

; [prints a space] 
OP CHAR 32 
END | 


TO BLine :num 

; [prints a blank line] 
Repeat :num [PR []] 
END 





Term 3 - 1993 27 


New South Wales 


Bibliography 
Abelson, H. and Sussman, G. J., Structure and Interpretation of Computer Programs, MIT Press, 
Cambridge, 1985. 


Cormen, T. H., Leiserson, C. E. and Rivest, R. L., /ntroduction to Algorithms, MIT Press, Cambridge, | 
990. 


Courant, R. and Robbins, H., What is Mathematics? An Elementary Approach to Ideas and Methods, 
Oxford U. P., London, 1941. 


Crandall, R. E. and Colgrove, M. M., Scientific Programming with Macintosh Pascal, John Wiley & Sons, 
New York, 1986. 


Cuoco, A., /nvestigations in Algebra, MIT Press, Cambridge, 1990. 
Dromey, R. G., How to Solve [It by Computer, Prentice-Hall International, I.ondon, 198Z. 


Graham, R. L., Knuth, D. E. and Patashnik, O., Concrete Mathematics, Addison Wesley Publishing Co, 
Reading, 1989. 


Harvey, B., Computer Science Logo Style, MIT Press, Cambridge, 1985. 


Knuth, D. E.,The Art of Programming; vol 2 SemiNumerical Algorithms, AddisonWesley, Reading, 1968, 
second edition 1981. 


I.ewis, 1'.1)., Approaching Precalculus Mathematics Discreetly. MIT Press, Cambridge, 1990 
Ribenboim, I’. The Little Book of Big Primes, Springer-Verlag, New York, 1991. 

Rohl, J. S., Recursion via Pascal, Cambridge U. P., Cambridge, 1984. 

Other books that may bc of interest include: 

Boecker, H-E., Eden, H. & Fischer, G.,/nteractive Problem Solving Using Logo, Lawrence Babann 
Associates, NewJersey, 1991 


Burke, M. P. & Genise, L. R., Logo and Models of Computation, Addison-Wesley, 1987 


Eisenberg, M., Clinger, W., & Hartheimer, A., Programming in MacScheme, MIT Press, Cambridge, 1990 
(a PC version is also available) 


Friendly, M., Advanced Logo, Lawrence Erlbaum Associates, NewJersey, 1988 
Springer, G, & Friedman, D. P., Scheme and the Art of Programming, MIT Press, Cambridge, 1989 


SPECIAL OFFER!!! 
Even with the changes to the Computing Studies Syllabus the Computing Studies Resource Kit 
‘has much to offer. 


The CEG is offering the kit at a special price of just $50 while stocks last. Get in early to make 
sure your school has this valuable resource! 


28 Term 3 - 1993 Information Transfer 


-omputer Education Group 





DELTA: Design Environment for Learning Top- 


Down design for Algorithms 
Trevor Barrett 


(This article is based on a workshop at ACCE '93 
about DELTA, by C.J.Webb, which was presented 
by Trevor Barrett.) 

Introduction 

The purpose of this session is to demonstrate/ 
examine a software package called DELTA, 
which is currently being used in various schools 
throughout Queensland in the teaching of the unit 
Algorithms and Programming in the senior 
subject Information Processing and 
Technology. 


The acronym DELTA stands for Design 
Environment for Learning Top-down design of 
Algorithms, and was developed by C.J.Webb of 
Griffith University, Queensland. DELTA is a 
C.A.S.E. tool to assist in the development of an 
algorithm for the solution to a problem, and the 
later translation of that algorithm to an 
appropriate language. The program runs on most 
I.B.M. compatible computers, and while a mouse 
is not essential, it does simplify the use of the 
software. 


During this presentation about DELTA, my main 
aim is to attempt to convey that this software 
package is a very useful solution to various 
problems which can be encountered in the 
teaching of a unit on Algorithms and 
Programming. 


In the teaching of such a unit, I have frequently 
found that students and teachers can tend to view 
the coding aspect af the unit as its primary aim, 
and rather than conveying principles of algorithm 
design, the unit becomes an exercise in learning 
about Turbo Pascal or some other programming 
language. 


Indeed, it was not uncommon for me to see the 
‘formal’ algorithm design process occur after the 
coding had taken place, so that the flowchart, the 
Nassi-Shneiderman diagram, pseudocode or other 
algorithm representation methodology matched 


Information Transfer 


he code which had already been produced. 


In using DELTA to develop an algorithm, the 
student is 'forced' to focus on a problem solving 
plan, such as that devised by the mathematician 
Polya i.e. 

Define -> Devise -> Test -> Revise 


These problems can be expanded as follows:- 

(a) Define - the specification of the problem 
in a form suitable to a computer solution, 
and even to consider if the computer | 
solution is appropriate in the circumstances. 
An ill-defined problem can produce a 
similar solution. Generally speaking, 
problems that are suited to a ‘computer 
solution’ are those where an answer (output) 
has to be produced, after some data (input) 
has been supplied, and the necessary 

_ processing is a task suited to the computer. 


(b) Devise - the development of the solution 
to the problem - the algorithm. In the 
development of this phase, DELTA uses 
Structure Design Charts, a combination of 
Nassi-Shneiderman diagrams and tree 

diagrams. The algorithm for the solution to 
the problem is presented in a graphical, easy 
to understand form. | 


A Top-Down design process is employed in 
DELTA. As well, the software provides for 
Djikstra's theorem which demonstrates that 
any problem that is solvable using a 
computer can be specified under constructs 
of sequence, selection, and iteration. 


The problem is first defined in general terms, 
and the student is then required to 
progressively break down the task into 
smaller and smaller sub-tasks. In so doing, 
the student must consider whether they are 
dealing with concepts of input, output, 
assignment, a module, selection, or iteration. 


Term 3 - 1993 2 


New South Wales 


ly one phase of the 
ally brought home to the 


Students when they first observe that their 


ing is on 


entire process is re 


This fact that cod 


tructs. 


that are used in DELTA to represent various 
programming cons 


The following diagram illustrates the symbols 





















































SSO : mE CERO Serer acce RS Bers PION 
2 9 oe a EE 
Po uw 2 3 cess ee Ss SRN § os Bee SOs : 
oe 2 2 eRe er POOL RENIN SON ROE wm Sey » <i SOD s MM SS -e i 
228 2 ao So 3 s SE o ee ase Bees oa Se Ng 2 = Rae ree ea : —_ 
S25 8 a s2 3 o SOE SSE ee ee 81 So Sa # 
393 4S 2es 3 5 oo B.D ge : 
>, > < ie Pu Dw 2 wo Boas SARS Seas Bos os a & es s 
aige 88a FESS FES2 - oe hE eS OU 
vn = By 7 oe @ oh + SOs 5 a = ov See 
S29R Bas ta 50 Ea ge lle oe Sue a 
gigo 28 = 2588S B88 Fey ies b gAR de : _ 
a ° a * Be Be “3 = <4 x Aer ares 
eo < OD 5 = 8 5 3 = g S = F = See hea 1555 5 = . oo & CRs oe 
: Races o S) Ae OS 
E nd a= yer a = ‘B as ) oD E e = a a” SSS a ) ro SS = 1m ow" Lo : 
SA = 4 E = ptt s = 3s &Y oo SF 2e «6 gE a ae z aie ot 
wy en tT om! . a) a ° nm SESS =|) rz - 5 me S| a Sea ee 
oD oe ) a mom A Reeoig)| 5 2 is wm OBS Bee oe 
2pEE see 33655 g8ea. et GE ee a 
ag 2 YD ee es 3 eSeN8l|5 2 eB 5 xe Se Ses = 
T ©) — 3 = a) Oo v RR Bax an & 6b UY ay yee Bawa 
& — i S SS oO SS ® —_ ¥ a o & 4 x | = : REG ro 
oS cs nae BS ogyV gs wea Sela ||2 = 2 S/O GE dan Se Bere 2. 
Feed ag2% SB -er 42e BS Bees ye sedis o 2 oa oS 
RPSbsSs we ge EG2esg wiStygee gis ik SS feet, e 
Sieg ggf5 25582 eve i) ite eos He 
: Py of 6D eo WY mo Re wy map |" GS + “¥$ 
wa oY) 6 & “ GY Ot ee Co SN nyo ag 
iB) = S) Cad ad & = cw 3 z = 7 a go a S oo) Reed nos 
3 br: aty52 © 2oUts Zaces ae EY eta 
nae 2 = - SSS = oe pe Rig ~ 
es Bp ‘o BF 2eongd ‘oo 3 Ff rE Soe cee: S =f z 
Wm SESS Gb 8) BERR . 
= = =| oe iS a O80 oO © Qs mat See 5 RSE i= Sas x —| Rees re 
=} ro) @ a BD) a=) = By & a) X a) Sa s Se 22> SONS » a Re Ke , a Poa { Sees ka 
—. = rr A [= > 2) X E _ uo) © Q e SK > oS SEES . o is @ Q ao GER is NOK SCE SOLEIL ; 
34 8 YQ Qo 3 o ms SS - v SIS RRC Comes 
Sask O83 AREZ2E CHEE SB 8 intl AU) Bees UE - 















SY 


MS OO CO OO 
RUSS RU UREN IU RRR COO ; 
OREO OREO RELL LER UCN ~ 
ee 2 cn © 4 os co 
Ss mi Eu og S a. B%o9 € § oY = a § 
pas SSNS <é Sey ‘ 5 x eS S SSSR <9 ene Le . Brew) . “Dy re | a 
GLEE % LUCE oOo 3 5) 3 Ae 7) oY) ro) 
~ Bes a Poe CS a fe & Oo n > 2 9 s > 3& as Uw w s = 
SNES ORs Mo SSA Reni on uo} -~ oy on 
Ss ‘ pa oa 2 SS ye SBA ESES SEY Son s224s§ 
Ks ROSAS Stes SERS 3s 3 $ SS } a 7 9) ! A Y om >) > ig | — v2] oD Song om A S @ 
Ss Sa SSS Sin 4 % $ % © = ® =— z = © — ‘~ ran} , A 
I Ase ok iS au” 8 o— Oo e°C58e °° § Be 42yog | 6 
SCE & pte « ES sek 6 cm) Z2woto Ra O'S Ep ~ OS Ane 
5 & Rd % x OD reat Oc Ow = s) or 
- i EY ont < ss s rt) >) e raw fae #2 
a. 8 § % RS oO -ao ‘ oO FJ oD) Ss @ yo an = oO & Som 
S = Be 2 , 5 < & Y © 5 2 & hae A) 7 @ -F 3 2 5 @ $8 S A 5. une o>) = 5. Ny 
x x a ty 3 ee 8 w co} ‘co Ses iL, = 4 — « = eo ro) Qk U on 3S 
ee : s 2 ee “i 5) ~~ 2 se) 2 BVA oO a oO ~ oO sg Oo = 
- » 4 K R —_ fox es = = , fr ® hd = 
& | % % Re > © 4 S 2 oP) co oo P = A “ OQ -m=m bf 
3 : cc 3308 ¥ Sees eee geSeeas gES& ax WF & 
Ss % 2 RS D mT os = C= w A ae om Oo 3 O - = om 
of % g % eo 5 oO ed sok w oOo & S S —,* oD a aA 
% Ral % % 8 nal A a an ao] an Cos YO = &D be 
a A , x > ree when | aa ro} @& ‘o) ~~ 3 jm j 2 -~ 1) ° © ~~ Q > + 
ae : Ss % - af ae a= 5 CS e) 5 ao 
| % ; ‘ Cu wn a <=} = Cc ron z = = BD: “aA On > 
< 3 5 : ae © a a or as = 2 > © 2of 
: : ; : oa S5ayS Bpar38 -22 Ow @6 wstbets®: 
3 Z ’ ed. < ~~’ © S So 
x 5 ne EE nae & o COEUR SSG RPASRYMG gy © ~o* Poca 
geo Se BSS BRE Ee SESE ot ESE | 6S YY PES BESS 
oa a homes © SOF fie m0 O Zz a ES Ce et OD & 6g ae =~ = Q, we 
are 4 MOS % y ~ Dy 3 = : SCO ww Q 
ac ‘ an: ob q 2 & ¢ Bes oF Zs cv oF ¥ E 2 
+ $3 i S ig Be = nw a | @ Cc = Oo 
aS ; < B ss : = GS 3 a A = ) = ~ 
ee. ah - SESSe DIzFESPESTSESHEE 288 22 Sstgs 
| bf fe. EF SEZeh Se¥SESETRERF OSS FRE 2eES S38 = 
BE SSSA 9 % Si + em SC an) am ; om «8S -_ = Q T 
wa OS ORESE a S % PO te & Oo 3s & Sw oD S WY 4 —“- AM © 
7 : Oo nore SSSees es ES PE8e8 ~Sai vgtSBeBE 
SN RNR ALAN - : 
Hii - 2 eglpeas 
ES Rend § Reece os 8 5 os 
SSI SE SOD % REEL TOLRE 
oes ee mS eFasarvs & 
See ee OST eS SEI SEE 


q 
4 Ss ve ex 
CLA K (2 o y, 
LP EES ESI NESSES SI RESOS 
OR TREE EE ERIK ELI SINE ALES EK PHeRON LES ISS 


Tt Sete 5 ae eee 7 nae ia EP 


Information T1:.. 


Term 3 - 1993 


omputer Education Group 


about this variable are entered. The subsequent 
box to read in the second number is developed 


DELTA detects the variable Num1 and details 


similar way 


ina 


NNpNNY 
weeeee 


tpt 


‘ 


PELE, 


N*N4 


weveeees 


e 
> 
9 


Opt lons 


Edit 


b-tasks are outlined as follows 
ta 


su 
Structure 


The three 
File 


rei ge 





Lthf 


AAA AA 
Heatly 


ALA AARACAP TAAL 


CN ERNAS ANAT REA NR 


Pee te 


S2estirigt 


nunke 


rs 


Structure 
FESR 
Buss 


Pore Poege 
SAAS ENS 
POLES PEL EEA EE 


le 


ES 


PoP” 


Fi 


SOCAL. ¢ 
SNANSASSANSNAZAS 


CEPLLOOPEIELIOEE DE 


SD) 
rae CARLA 
Sse 
APPLIES TEES LEAL TOE, 
NANNEN SNS ANA SY 


NYAS NENAS reece’ 


NEARS NAINA NEN SERA 

REAR APR AACE AAR ARR RALRA LADO 
PSRSERAN CAN 
TRAPRALRAT AAR ARAL AREA 
SENN CNR ax 





COLEE, tent 
fait LLL AI CL lf 


Xe MOEN 
POOLED LT P 

feed 
Nye 


teN 





ernersys Ay, 
LOPE IRL EPL EY 
PN ENANN ES 


a 


hee oe 


aa 
ants 


a 


PONE AMA BN ae, 


z 


e whic 
te 


ee, 
us 


ADEN AA NACA AA SA ere eee 
“a 


alee 


Weeege 


LE LELS: 


te 
ALO TELE EE 


POPE ETL LALO TE: 


ty tee 


SE ANUS TANNA 
RNa STENT SNTSATS 


SAAN 


LMOMPLILE MAS AL CE EEE 
x Cty cead : 


fall 


eee 
SSG S SELES 
reese 


NN, 


SENN NS 
ELEN eye 


ase NS 


Le 


OOEAEL LEE LE aE ALLE 
ary 


eted be eg 


eeres 


Age 


Apes 


Breer 


ee 
wees 
FLEES? 


Esc to rcturn 


Enter to cdit, 


NNN 


ye 


then further developed by a 


similar process, into a sequence of three further 


sub-tasks 


: 


18 





IIIS 
CAL af 
Ce an$ 


The first box 


Ny 
CELE EL? 


00% «Move with the arrow keys, 
User T. Barrett 


raat 


program Haxialsc 





sis 


te 


ater. 


: 


Pr to @ 
r} ntaS ¢ 


is gre 
AEe,E 


h number 


ic 
done as a Selection 


ines wh 


The next step is to develop the box which 


determ 


EEN EES OMA ES EN 


r 


” 


a 


OWED AEN EY AY PEN AN EN ON AS 


ve 


NpaNNy 
Wee tee 
A! 


Clect ton 


OMA AAr 


4 


tat 


Le COPEL ALOE NOPE E EAB ELL ult 
OS RAINS Soo 
PLL LH al LLL webb 
COLE EEE EERE 
CLLLOLLEEO LE ETL LAA I ALG A 
Leg a4: tat 


DA RASS, 


¢, 


rater 


ry 


f, 


SATIN 5 
wag 28 tne first 
= 


ay, 
3 

“ 

cA 

* 

4 

4s 

4 


3h 


NAN 


a 
SAS 


TA 


wae 


as follows 


IAT NINSINT NTN STATON RNA NT STATA NAAT 


Clear the screen 


+0 
va 


a 


arn. 
aeeey 
aed 


Ry 


‘ee 


iB 
~ 


LIL 


A RW NTRPRSANA BA LAS SRSA LS SPER A 
% . NA ee OOP LPEPIL UNE EOL POEL LL ULE, 
« PRIX ARAL ALCAE ROE: ‘ 


“eek 


fon if true 
fon if falso 


Ip 
it 


Gs 


RY 


ene 


ANSNIANSNAT NESS 


SPPLP RITE ES 


ara 





LPL EL OLE LOL ATT 
TAN 








yxoox Select between two or more different tasks 





CPLLEEOL OP LE LEELA LEP TL AS ALIT NE 





NA ANNES ERS, 


Nd eREASSANERN SS UN SANESS 


SN ASSS A ASENS 


SNS 





PEARS N SERN 


COLE tlre 


NEN Sas SENSE NT SATAN, CANA SONAR 


*e 


VLEET er P ed EDEL LE LIEL EP GET YEP EOED LL LEE L DE 

SIAN I AS NaN TN AN ee EP PON ae PEED OPEL EOE ED LE E™ 

LOLG ADA DAOLOIEEETGLE LS 

AN NN a eS SON 
ELE 


MAEELE EPIL 


Typ SBS SANNANS 
Lappe ty POOP PRE ES 
Nyy SNR NANN ASN SNATNING 
CREOLE Pape 






PLP LE MEP TL 


tot 


. 


‘ hs eae tata 
hy SESSASNENS TRA NSS NSS SARS USN NSS BARN ORN NSU NSS SN SRN SSA BOSS 


WNTNSN 


SAINT SANS 
SPREE ET Pat 
A 


Ata 


ARAN 


CREE 


sake 


Se Keer 


vy 


ere, 


oe 


9 


ACARI AMARA 


SNA NSASSAN INSANE R SONS 
yy, 


3 


Options 


ta 


i 
ies 
Sher 


h 
RiP Rea pnatats 


i 


~~ aNNANRAN NN 03 


Pri) ys 


IAM ATTA APR ATTA 


LE 


CPL EELLEE AE 
ANAS ANNON 


nd 


ett 


eA at ELS 


ae the seo00 


Tae ™, 


< 


SPLILEEL LR LE GEE CL Ot 


bo 
a 
2 





nm 
aniekY 


: 


fs" 


@ whic 
a 
to 
in tne first 


terni 
ha 
r 





PS PP ra . 
POE SALSA OAD A OBO EOD AED OD Ob APN SS, 


pm PAT AANA NA AEs MASA 


Ss 


Nee < 


LAST AELL hgh 
XMLASANZ RS 
aN 





CTP LFA PAPE TOO D 


NARA NNT V a ONE RA ts SECS ENE hs WOR, SCE 


Opt fons 


h 


LOLOL IR PTET A TERE 


ta 


7 
NAN 


Da 


it 


Entcr to cdit, 


progran Haxinise 


we 
ay 


developed as an Input 





1S 
Structure 





File 


later. At this stage, the box to read in the first 


The box to clear the screen will be developed 
number 


>< Hove with the arrow keys, 


er T. Barrett 


Voor estes 


awe 


1s 
ngs te 


BF 


~ 


© user és e 
that) tal) 


” 


& 
eee 
a wv My 

y al 


_ 


xe 


var 
ae 
an: 


isiaa 


i 


CPEPL PIE LL A 


is 





Hon : 191792 


progran Maxinisc 


NEES 


bj| Ureapt ["Hieasa enter the first mimbher 7 


CPAP L EEL EIT a Eee. 











Term 3 - 1993 31 


Information Transfer 


New South Wales 


The next step is to develop the Output phase of 


the program, as shown below 


t operation, as 


ignmen 


The left hand side of the Selection box is 


developed as an Ass 





























































































































































































































SSRN PRAM RR RICCO “<< SS 
secretes ‘ bt Rea? 2 ‘. SMe. bomen $5. 5.99.5 5 ated OCC ICDL So a2 
POL TI SCORCH, CRT bad ORR sd SSS mame 2, SPOONS EOD OY Q 
ONES open one Eee SECESS 2 : SSDS ENN : 
EOE A} % ‘s 5 ee, . @ So ORNS x 
SOS SASSER ~ es , = = Cr Ronen ee on RR > s 
APE SSS SS NTS SAS Ay = . oa <4 KL ARAG ; 
on Bannan = Be fs 1 i on Bee < § oF al SSNS ~ ‘ 
SSS Se -_— ~_ a g Tee iz SSK OSES ESS ; 
Soot IF RLg= 25 eS ‘ E See ‘ 
PS Ae eS x epnine 
ESSN DSCNS zi < = S58 . = oO , SINS RIE See 3 
LER LV RAR ATA RAUL ALA 4 ~ ¢ Ms 4 
SAO Wess E Si : 3 eee : 
ONO een cP LICE 4 Ee sf — ONS % 
ORR SER . Roe é oe Recerne i ees 
SS SESS SSSR ‘ Das ne 6 ee LOLS < 
2 LOL < 5 : = i] oe 2 3" 9 Sess aK > Sa: SSNS 
2 2 he SELES, of, SSN “N e 3 D ~ LIRR “sf 
ASA c RRR RORE AAS SONS es 3) Shige ; SSE Ss wn = gi.” e 
= bs, PRE op Mere ‘ YY = Bue « 
% : errs < <4 =» a io Lapabe 
> - . 4 
s a ¢ ;: < 5 ys Pa eas Fe 
{ —) © yhhe ? tow 
Suse git i: BS nm a 4 go 4 Ee Se 5 
y 4 # ara he % ros Yeke 4 3 = : * : 
qj ca . 
ay OB hse i Re ) aq °7z $ i Ss wo iow 
4 A @ Jet A <a A wo Sion “ q ~ Vier 4 
3 ow : Py p iz q 5 4 
ost, re me Ba gars 2 Ba 2 Ee : 
‘f. 2 » 
A hace ter NE : A se ‘ = 3 ob Sut 
f WRG < 4 < 
its Haw zi : 48 gist 7 iS) asi 3] |S! |bpoemmets 
q x ¢: 3 oS vf J. LES 
ad $y, CH ¢ : “4 4 3) | RRS ¢ < oO, eee Brn 8 
Mais Hes RE CME. 20 eve , ROME ~ Yeu Sa PROERRR 2 
14 242 im + ** Kalk ‘ CNS ag baa | wo Seva 2 ale Renta pad om ST ! | 
ha SY hdd 43 a EEE ES CREEL SEGUE y az) =H g x p> P| A= . ns = 
¢ 4 . » r, = 
3 4° f Nos ‘ is = Bou il J oy ‘ - 2S 2k, r 9 5 
SE hep B o Oo Sete ; : ae 9 3 O ays - 3 a 
adi ‘ : 3 = ‘ : 53 > 
% AE Hs = ; , Xa wats. a 
At sh yee = aq od x3. $ ~ | -_ YQ 24 8c ig ko Ge e 
SEED gag cy a 5 > & 7 o acs $ 8 Ba ee = = B Sows =] mS S 
ran : Joces } 
SY be (ina Pe Ea O Oem O S Ni oces s 2 = # Ese < 
J oc et BSCE SEES Bt | a x +4 : oO =% 
cau ; i Seti Us 5s o arts ; By 3 2 Eady = 
. ky z <4 & "od Sy ear : SS & aa i boned 
R Gaz "s bi ah = i? 7) i 2] Sue z = oe . 7 S © ana % Ens 2 = 
but 223 Whe a N3s x om OB ra = o Ka SIS tae “ we = +) 
a sents $ TNT rei Lue eS 2 -_ Cc > a ‘ $ & ver = BESS Ze O ba a . % RIE SEER = 
rd * } ier ay A ’, 3 => ot Fs SESS $ 
recent © ; ES 3s OM 3 G8 S| = je oe =e Sw SSRN = 
SESE EES $3 s Ppeee I EMTs = o XE Pen} Sais S So x 
RIOR z Sar i= RS Rene ae Re o Ss © BER eS ¥ 2 <eore 
2 Eee Reel 5B QB shee = BSS Q v =e | BS “ § 
RRR g eS m= LR es w tas PE os es} = » 
a SE NES: : : REESE = yO fe en) SRS OES ROS cf 
SEEKS SAO ASS = ~ jo) BP) faa 3x? BIEL tome » EEE ALLE, -_ 
Bo : By ee Res Be 2 a5 Son | SF 
RRR é wey .B) Oa SS 8 oO: ome ROMO OR AL Tad " ; 
LODO CPC T LOL OT, 2 Ore. v4 ge >: SIS Sys % ; 
y Ss SOAS Dry rN Oy . y = a Se are SS Dy = * = SKE NSN s | al 
ISSO, ¢ <r hee = x Se Oe oe c= ra) SRE au : . 
4) SAP ae roy SO > te ~~ hss y SS Ny A . i? 
Son fxn) 9 oe ; ees emma SF 
GLé! i a hh ‘ = -, ">> 
eine: Se SN rer arrnenee CLR IR ROE ODPL LREEL LULL K ee ‘ 3 Sie : 6 RR SIRES OER Soe 
Py See eee CORE SORE, See TEP LEE Ane ere ee 2 “Ss yon Ki ies Re: 4, EE SEE LE EES ae EER CLEAR ELE 
LP Bere SOS RL ECOL UTERO RDM EEE 
eT $32) SASS SAME oo<s. 
“ " C53 & at 
AEE SSS SIS HRIRRESSSS = RES 
KA a Ss NOSES SLES MOSS af a ee 
REN ARR PORNO Eee = 
E SONU 6 w= 
#685 cs REN NeRR NN pekor & ~ S2e 
° te uw See eR es ‘ Began 7 | 3m 
a : &eg2 Cn Re SEas3 He 
233% SESS gies 5 0 @ 
ha — cc ‘s SONS SNS <3 B = o i Lo a | x 
43 A ORR 2 n = rs 
? q oe ENR z 3 oO D & 
3 a SEA SS SSDS SASS SS . g = -_ S 
‘le ea LEER ‘ RS c= : Ss a3 5 
Oey c= ae| Sn g % = OQ. ws + =. % 
° : Poe ah | SSS es RCI LLIR. ot rs | O SMc2 “ & 
A : a3 : d : 3 : = 54 23s S 
% de : 2 SS 3 2 pe Pe om ~ Bonn ons % 
5 oe Porras 3 = 8 $0 : w oP) a on me O te D % 
* oh P3 ‘ SS ony bad g me t : % so U > O aba & 
3 Het : y Sick 6 £ s iB} 5 Peg x 
‘s z > So S GEE z 6 ay dean] 
SS 2 r ned Bd 8 on 2 * S =~ m1 C&C % 
Ss MOL IPA TALS Md % Siew wwrn % By ss 2 83= 5 ‘S 
: ‘ % 
iso} £1 $3 Hare : g 5 Ry oh c % Ot w Ad x om bee : 
aa os Sow" S25 ye ie mm Sd ou- sp. re = o— Ss be % & 
TB Sues, Er YF % 4 + heey ri . BS QO vo Bucs 5 i 
~ ‘ *, . 4 “ ” 
oO AF tf an 17 Y ay GF ; z 5 Sw Sots = s 
<5 so ‘ a 4 . ‘ S R : 
joes lay? 33 oy sass Hetil : k 5S Sac & ce aa 
oS ee seth 1 oe ESS QO PS mid! = CMLL CREEL rt ~ Sows ‘ as rr4 
eee We + ii CESS te ohn ye 4| 2 PEO a) > — se he muaeenaee Ses} 
~ io" es EERE LIOR % rat “ ~ Y 3" x z COOLER % - wo Cc ES fy i! s 8 £ 
6D = Sle Mt 4 a ram © ; & 
Sas ens Ko > Sas Hes mS = 3 = : 
Ber ave ‘ ra ty : x =e Sct 2 s 
. 2 qnté & | 5 a oe & x 
> 9 fits ft ss can: : fog me: is 
8 eae x % ke c x = ob) SEED <S . 8 
a3. ene ‘ in3 ‘ OS = eos = < 
o>) 53 ED z ak Ne eS > Ch 54 be oP) g a ee " 
= Rss ave de: Ss Sag ; ; > O SEA § 
asi, - smomunmm§ Re Meet, Bis aa SOA Byers SE 
eo) Eran ‘ A? Re 5, © Nise ; FOL ~ 5 teas & 
Seed bx 3 ky > py On $ & QW be % BS | ~~ % 
5 hehe ae g ae S iy sa i 5 2 2 & sient s 
2 z 
QB ShS ss : yee 4 an aS Fes ; 1 ‘ 5) 3 S nese S 
a gz é LEAR HARROD z So ws z : ‘ ROMA SS 
od < ; : se aad : : 2S Rass x 
¢ 4 . 2 SESS AI é 
é eS $ ; x s 5) Oo A> RR 
S g x ‘ a £ © Oo yy LESS <v Fr had 
: ~ 2 i < 3 —™ 5H OSs ss ~ 
om Q : “ § ot Ck 2 ~ ; % wT oO vu es = eS Ses 8 op 
Mw = 2 Se kt - S Pa < > se | IN 
*S S> x < 4 
aa : Be = ce 3 % 3 nA oe : a 
y as \ ¢ ASIN TSS SS i: 
¢ % 4 SSS AES. S ? i=] | a COE CLS 
* » LES EUR <% sd — epee er z ri ‘ 
= a: i we Ce ‘ a a oS So : as 
—_ Ki S ee. Ma 6, SPAS SS MN e ee 
= laed 2 & te y RES os 2 § tn jaa ey SRN LEOLLO VED LLY AHOLD URETE LE 2 Net POY D ax POI Ss 
OURO DTD ERED TRE BOSS Ss v v om IL RRR REIN RNS SRR y ee * 
>) SRO NS rere SRR IRE SORES Re 8 REO ONS RU IRI 4 Ad aa AB BO OA RO ES 
Va Be eR SOA MRI a RS Se 
a 4A ON 8 EN Sy re fe . 


Information Transfer 


32 Term 3 - 1993 


omputer Education Group 





Returning to the clear screen option which was 
by-passed earlier, this can be developed as a 
module (as ‘clearing the screen’ is actually a 
procedure) 


RRS AA 
AYO EN GN 





4 CRP OP ORIRO NT AL REE PANN Wes 
NIN ARNON ONO OR NOON ARABS EN a NANA 








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0% Develop as a moduic with its own structured design chart 
User fT. Barrett program Maximise 








We declare the module clrscr to be an imported 
procedure from the unit CRT 


File Structure Edit Data Opt ions 


























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ARRAN RRR ACRACH greater, and reports AR MIG ISS 
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43 


We can now test the algorithm by choosing the 


Trace option from the Structure Menu. Trace 
can be run in Step-Mode, or Fast-Mode 


Structure. Edit Bata Opt ions 9:Har 



































4 af. ‘ 4y4 Faded, 4 ALARA: 
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»~oo Trace through the chart showing variables. 
User T. Barrett program Maxlaisc 


Information Transfer 































tom : 190416 | 


ni File 


The assignment of values to variables, and output 


from the trace can be followed on screen. If 


necessary, the Structured Design Chart can be 
modified, and Trace re-run until the output is as 
required. 


Display Fast step Quit 


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User T. Barrett program Maxinisc Mem : 165136 


Finally, the Structured Design Chart can be 


translated into the chosen language, in this case 
Turbo Pascal. The file is saved to disk with the 
extension .PAS 


Edit Data Opt ions 9:30am 


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ON ENON ON INOS: 





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Program Maximise: 
(This program asks the user to enter two different 
muabers, deteralnes which is the greater, and 
reparts the findings to the user} 
Uses crt: 
{clrscr fs imported from crt) 
var 
Num 1 
Naum? 
> Teal: 
begin {program Maxinise} 
clrser: 
Mrite(Output,’Please enter the first number ’): 
Head inCinpet,Msmt): 
MrileCutput, Please enter the secuml number Wiffereat tu Ue first) ‘ 
Readin( Input ,Mua2): 
If Numi > Nua2 then 
Mase := Phil 





eee 
RAT INR 


oo Translate this structure into a programming language 
progran Maxlaisc 


User Tf. Barrett 


Obviously, we have only had a brief look at the 
DELTA software. There are many other aspects 
of the software which can be explored, including 
the development of modules (user defined 
procedures and functions, and imported modules), 
built in functions, arrays, records, files, etc. 


From a teaching point of view, one useful facility 
is the Playback option in the File menu. This 
enables a teacher to prepare a problem 
beforehand, and then playback the steps in the 
development of the Structure Design Chart. 


Term 3 - 1993 


TR NT TS Ny NS NANI NEN NANNY SEMAN NN ERAS NGS NY 
PPR IRD PPR LPS RPL LASTS IERIE ERLE ESATA RE LATENCY SERRE ELI RE ON. 





33 


New South Wales 





Example Task: 

Use DELTA in the development of solutions to the 
following problems:- 

1. Read in your birth, the current year, and determine 
your age in years. 


CARR Any 4. A, uy NN AS 4.4 
ARRAS NAGSG 4 Load BRAN RANRARRAS NPRANNE NANI SRI 
a 
& 4 on 
y 4 New be 


ete Pe ks the 
AST Mt ch POEL Tae ae 


» File Structure Edit Data Opt ions 9:39am 

















2. Read in two numbers from the keyboard, and 
determine their average. 












NZ. 
AAS at 
NAS 














NNN NORDIN 
IS $ 
NANNY LVN WAN INN EREN EN NEY EN LUA INN NEE DNA RS i RE NAG * a 

4 termine which nuxher result to 
zt weet, «aad » x 
ig value te vam s 
Ore 








PlayBack 
fibou t 


SONS SSH) 












Exit ALt-K ‘ 
. es $3 
3. Write a program to convert degrees Fahrenheit to . re ze 
4 a 4 
1 > q Ray Ww 
degrees Celsius (9C = SF - 160) : f a i 
ox NY e EAN g 
AS s * NAN 
4, Write a program to read in a number and determine a Nicee a pest bE AG 
aoe NARA BAS BKK as 
ABS SEN Bae wan y 
the square root of the number. (SQRT is a built-in NR we RS ie aM 
ANS yee aN we ; 
a e . o fy 6 q 0 , 4 y 
RNS Lex : wy iN: Me 
function in Turbo Pascal) REE a RANA AACA RAAT AWN ARAN ARAACRN ARAN RECRRANO 


oo «Show the progressive stages of a previously developed chart 
User T. Barrett program HMaxirisc Mew : 184120 





A new version of the software is under development, and this is hoped to eliminate some possible problems 
with the current version. For example, the Trace facility cannot be used with Functions. 

However, as a teaching tool, I believe the software to be particularly useful. 

Any persons requiring further information on the package should contact: 


Structured Solutions 
P.O. Box 859 

Mt. GRAVATT 

Qid 4122 

Ph: (07) 849 2404 


Acknowledgements 


Webb C.J. (1992) ‘Structured Design Charts and DELTA’, QSITE State Conference Proceedings 1992 pp105- 
115 


Gordon C. (1993) 'An introduction to DELTA’, QSITE - IPT Teachers Conference 


Carey D. (1993) ‘Advanced DELTA Techniques’, QSITE -IPT Teachers Conference ) 





Term 3 - 1993 Information Transfer 


mputer Education Group 


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Information Transfer Term 3 - 1993 35 


of RAM are configured for quality presentation of 
all Acorn CD's. The monitor supplied with the 
A4000, AS000 and A540 systems is a high 
resolution, multisync monitor, so the visual 
resolution is high quality. Multisync monitors are 
available for the A3020 as an option. As well as 
running RISC OS Acorn computers will also run 
MS DOS with a software emulation, and, through 
an emulation card, Windows 3.1, and so will run 
DOS CDs and some Windows CDs. 


AMIGA Commodore run the CDTV systems with 
a hand controller similar to their game controllers. 
There is a huge range of ‘game’ type programs 
available for this system, some of which have 
existed in the education market in disc form for 
years. The system requires a player similar in 
appearance to an audio CD player or a video 


e a wien Sins 


BS 


player which includes dedicated computer 
processing and a television screen. The CDTV 
Player can be outfitted as a computer, by adding a 
monitor, keyboard and mouse. 


DOS There is a large range of DOS CD's on the 
market. CD's running under DOS will not include 
video or large amounts of animation, although 
they may include pictures and sound. Generally 
they have a large amount of textual information. 
Newer CD's may run under the Windows 
operating system. Many Windows CDs include 
animation and video clips, as well as sound files. 
The basic DOS machine may not run a CD 
straight away when a player and SCSI card are 
installed into the machine. For most new CDs 
including animation and video, a Super VGA or 
Multisync monitor is required, with a Super VGA 
video card replacing the existing video card in the 
computer. Some CDs will also require the 
computer have a Sound card installed, and may 
require that the computer have more than 4mg of 


Term 3 - 1993 


New South Wales 


RAM to give sufficient free space once Windows 
is running to control the CD. This problem can be 
addressed by using memory controlling software, 
such as that included in DOS 6. Video on DOS 
requires either the multimedia extensions 
developed by Microsoft, or Quick Time for DOS. 


MACINTOSH There is a growing range of 
Australian curriculum applicable Macintosh CD's 
on the market. Some CD's relying solely on 
Hypercard as the controlling program do not yet 
run in colour, or may not run in colour on all 
machines. Others which have been developed in 
MacroMind, or other animation authoring 
programs, run best in colour or only in colour. 
The Macintosh video handling program is called 
Quick Time and runs in a window approximately 
10cm by 7cm on the screen. The quality and 





resolution of this tends to be very grainy, with a 
tendency for the words and faces to appear out of 
synchronisation if the CD is running on a low end 
Macintosh such as an LCII. Best performance is 
achieved by running the CD on a top end of the 
range Macintosh - such as a VI, VX, Centris or 
Quadra. The frame speed is 10 frames per second. 


The minimum system for running CD's is 4Mb, 
however the speed is vastly improved by running 
on a machine with a larger RAM. A high 
resolution multisync monitor, such as those Apple 
has begun to sell with their new systems, also 
improves the quality of the image considerably. 
All systems need a stereo speaker system to 
handle sound well. The computer can handle the 
functions of an amplifier in a sound system, but 
not that of speakers. The internal computer 
speakers will not handle the excellent music 
which is a feature of CD presentations. Some 
systems include this in the purchase price of the 
CD player. 





Information Transfer 


ymputer Education Group 





Macintosh and Amiga systems are dedicated. The 
drives will not run discs configured for other 
platforms. The Acorn and DOS players are 
interchangeable. DOS CDs and Amiga CDTV 
CDs can be made to run on an Acorn with 
specially written ‘front end’ software. 

To use the CD players currently available for 
computer systems, the user must place the CD in 
a caddy, with the label side up. The caddy system 
is an obvious marker to the user that they are 
using a Computer CD player, as the case 
resembles a 3.5" floppy disc case. The real 
difference is in the way in which the drive scans 
for information on the disc; for 
audio systems the choice is 
between sampling the signal 4 or 
8 times. For Computer CDs the 
signal is sampled 32 times - a 
much higher quality machine 
mechanically. 


The difference between the 
audio and computer systems 
using and not using caddys has 
caused some problems, as the caddys are 
expensive to purchase alone and add to the cost of 
the system unnecessarily. The manufacturers 
have said that future computer CD players will 
not use caddys. 


As far as the user of the CD is concerned, the 
drive will appear and be addressed in the manner 
usual to that system - on Macintosh and Amiga, 
there is no icon when the drive is empty. Once the 
disc has been inserted, the icon appears as another 
disc on the desktop which is opened by double- 
clicking, programs run similarly, quit by pressing 
Open Apple/Q and ejected by Trashing the icon. 


Acorn CD drive icons appear in the Icon bar at 
boot up and are opened by clicking on once, 
closed by closing the window and ejected 
manually. The drive can be dismounted if you are 
swapping through a number of CD's. 


Under Windows, an Icon will be placed on the 
desktop when the installation program for the CD 
is run. Under DOS, selecting the CD drive in the 
usual manner (eg, F:), then browsing the directory 
of the CD will show which is the exe file to run 
the CD. 





Information Transfer 





The CD's and their Contents 

CD's are in their infancy - there is a growing 
number and a great deal of variation in the 
quality. Just as with books and other software 
items, teachers must evaluate them carefully and 
decide on their usefulness. Teachers more 
familiar with computer presentations will look 
past the massive leap in the capabilities of the 
technology to the actual quality of the product. 
CD's that allow the reading level of the text to be 
set at a more appropriate level for the ability of 
the students are going to be more appropriate than 
CD's that simply reproduce the text in an existing 
encyclopaedia. Problems that can 
be noted in books and software 
with cultural bias, sexism, 
inaccurate information and 
inappropriate content are all also 
problems with CD's. 


Bm! It is also necessary to assess the 
interactivity of the presentation 
Style, and the amount of use the 
System can reasonably take in a school. 


CD's are essentially information based. Many 
schools are seeing them as a library appropriate 
purchase rather than a faculty or class based 
purchase. After all, the CD encyclopaedia are 
cheaper and more easily upgraded than the book 
versions - as well as taking up less space. In a 
library, if one, two or three students only are 
using the CD ROM machine, what do the rest of 
the library users access? The long term plans 
could include a number of machines all including 
CD ROM Drives - as common in a library as the 
Shelves that hold the books are today perhaps. 


These are a sample of the CDs currently 
available, with some comments on them as 
program examples. As with all software, the 
content of CDs will change and expand as the 
medium is explored and becomes more common 
in schools. 


The Parliament Stack - First appeared as a 
program on disc. This program is distributed 
through the Education Office of Parliament 
House, Canberra. It is a hypercard stack 
containing information on all the electorates in 
Australia. The files include Census information, 


Term 3 - 1993 37 


electoral office information and demographics, 
and pictures of the representative and where they 
are located when parliament is sitting. The discs 
are updated every time there is a bi - election, and 
the updated CD is available as an upgrade on an 
exchange and small fee basis. This is a good 
example of CD's providing a large amount of 
detailed information that can be easily updated. 


Creepy Crawlies - This is a CD featuring insects 
- and creepy crawly thingies - much loved by 
children! The interesting feature of this reference 
book is that the textual information is included on 
the CD four times - in two different reading levels 
and two different languages. Younger students, 
or less able readers, can select a stage that allows 
them to access the information in a more 
appropriate format. The CD also has a picture 
and video file - in colour, for each crawly shown. 


Grandma and Me - this is the warm fuzzy of CD 
programs at present - the most reluctant computer 
user will happily sit and click with a happy smile 
on their face to discover all the hidden animations 
in the program. The CD contains an animated 
story that the reader or listener can explore. 

There is no feedback from the reader incorporated 
into the story, so it is still very like the 
encyclopaedia type of CD. 


Revelation - this CD incorporates a program that 
has been available on disc for some time - with a 
very impressive collection of files that students 
can use with the program, or in other programs. 
Revelation is a professional quality Art program, 
and the files included on the CD provide a library 
of photographs, pictures and paintings that have 
been digitised for student use. Students can 
manipulate the colours in a Van Gough painting 
of sunflowers, for example, and discover what 
colour the sunflowers really are. The CD Storage 
space has been used to best advantage through the 
inclusion of an interactive tutorial program. 


Animals - this CD presents a visit to the San 
Diego Zoo, where the user can choose from a 
map which biome they will visit. Going to the 
area shows them information, pictures, audio tape 
and video about the landscape and the creatures in 
it. The whole is icon driven, and incredibly easy 
to navigate. A strong feature is the video on the 


Term 3 - 1993 


New South Wales 


endangered species program running at the zoo, 
which is Over 5 minutes in length. Parts of this 
video can be quickly accessed when searching the 
information on an individual animal, thus 
providing a very useful video cross-reference 
index in the background programming. 


Beethoven's Sth - this is an example of a CD 
created by the music industry having the blank 
space on the disc after the audio material has been 
burnt on used for a computer control program. 
The small space taken by the program is enough | 
to allow the user to learn about the period in 
which the music was written, the music itself, and 
musical terms, phrases and methods as the Sth 
Symphony illustrates. Also included is a music 
quiz game. All aspects search and find the 
appropriate pieces of the music in the CD to 
illustrate the point being covered in the tutorial 
program. 


What will the future hold? 

While prophesizing is not one of my strong 
points, there have been several indications that 
this technology will have some dramatic 
contributions over the next few years. Indications 
are that more interactive programs are due to be 
released, where students will make a response at 
an appropriate point in the program that will be 
used to channel the student to an appropriate next 
Stage or section of the program. Resource 
material and syllabus material could well be 
delivered to teachers via this medium. Software 
developers are working to develop systems that 
utilise the medium in new ways. Students can 
now explore the Antarctic with Scott on the 
CDTV system, reading about the expedition and 
trying to manage their own in a successful 
manner. This type of simulation is ideal as the 
CDs hold so much varied information. Kodak 
CDs have become available, and some schools 
are already exploring putting commonly used and 
valuable pictures on CD for use in school 
publications. Clip art collections in this genre are 
Sure to become popular. Acorn, for example, 
already provide a clip art collection of useful 
video clips. There are also many collections of 
graphic design clip art CDs for the Macintosh. 
One thing is certain, CD programs have the 
potential to deliver increasing variations in 
software over the next few years. 





Information Transfer 


mputer Education Group 





Pacific PowerNET :A resource for teachers. 












John Attwood 
McCarthy Catholic Senior High 
Tamworth 

I was privileged to represent the Yr 11/12 SIG of At its very simplest, this setup will allow 
the CEG, and the Schools of the North West, at Computing Studies students to gain practical 
the recent launch of an exciting new electronic experience at establishing and carrying on echo- 
communications network, called Pacific mail and e-mail communications. 
PowerNET. 

Echo mail can be used by students for simple 
PowerNET was officially launched by Premier, "chat" with people in other countries. This has 
John Fahey, at an event held at Mt Piper Power implications for many subject areas. One 
Station on Friday, September 3rd. Mr Fahey was ex#inple from the @alrossy experience will 
accompanied by Mrs Virginia Chadwick (in her “demonstrate the ehormous potential. 
capacity as Minister for Education) and Mr Garry 
West (Minister for Energy), as he initiateda , | a A student, required to present a Personal Interest 
phone call which sent messages,of _ ¥toject for dsessment i in Society and Culture, 
congramiletion i to his two sind hi = oo -sPlaced gy réchib-p 1 lgsbage “requesting 


Following thiss the visitortaivea Gemonstratiog ; 

of PowerNET ih use by aera Yearl2 siu@entsss 

from the Calg@esichool € ‘o : th). The g with an international flavour, and 

have been 1 yore : triaf iif fe peer § fe real insights into the place of 

the regional, pub Wadestalfisked aff ihe sclpokm= | we meg in \ditics world-wide, In agdition, the 

earlier this year |; £F g & Fi an 4 adengawas < ple sto send e-mz 7 meg sages to US 
° "Telit fesident, Claus pausing the, White Flouse e-mail 


erate eieie a a ae 


| : bs flowed i in, allowing her project to 

























= 
* 
So 





By 








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cost, liande-on availability of ah: databases. : 
echo-mail and electronic mail facilities. 


The basis of the network is the establishment of a As well as the data bases, and the availability of 
Fidonet (an international, low-cost network) hub e-mail and echo-mail, there are areas available for 
in Sydney. Regional hubs, like the one games, downloadable software, and more features 
established at Calrossy, will progressively be are in planning. 

established at schools in strategic locations across 

the state. Other schools can then call into the For teachers of any subject, at any level, theres an 
network for the cost of calling the regional hub echo-mail area for you! As well as the obligatory 
school. The central hub will periodically update computer literacy and computing studies areas, 
the regional hub data bases and will effect there are areas relating to mathematics, 

transfer of messages to/from the regional hubs (at geography, languages (some in English, others in 
no cost to the regional site) and will conduct the the language), science, the environment, cookery.. 
international message transfers. to name but a few that spring to mind. 





Information Transfer Term 3 - 1993 39 


New South Wales 





As computer educators, you owe it to your allow for off-line reading of the messages and 
colleagues to at least let them see the potential of responding to them, you will also need an off-line 
this form of communication presents. More to the reader package capable of reading QWK 

point, you owe it to your students to allow them formatted and compressed files. For MS-DOS 
access to the combined wisdom of a few thousand computers, the comms package could be as 
educators, and their peers, on the PowerNET expensive as you like, but I have found that the 
network. You should start lobbying for a regional shareware packages are the equal of most 

hub in reasonable range of your school, so you commercial efforts. I use Telix by preference, but 
can be a part of this low-cost, high-interest, forum Procomm plus works just as well (both are 

for educators and their students. shareware). 

Your professional development is also catered Off-line readers are predominantly shareware too. 
for, with international and local teacher chat I usesthe OLX (for Off Lite eXpress) reader, but 
areas available. You can establish contact with any of the Silly Little Mail Reader (SLMR) 

peers in Europe, Canada, Asia, New Zeafand, . family will work wéll. Again, both of these 

and, of course, U.S.A.. In this way you tan keep * mentioned are shaféware, and should be available 
a handle on the emergjag issues frorti‘overseas p ata BBS neargyou (if one exists!) but I can supply 
classroom managergent and/or teaching strategies: A copy of Teli and OLX on ong High Density 
You can also be a pal ere — 3 th disk for,$5 to cover the gbsts ¢ of duplication and 








pasttge(MS-C y Q )S*Only ). 


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Frequently asked Guestions FAG ae at tthe launc 
concerned how much the access was going to 
cost, or how much equipment/software was 
required. The answer, for most users, is a 
resounding "VERY LITTLE!!". If you don't 
already have a computer at the school, then you 
will, of course, need to get one that is capable of 
operating a modem (and that includes just about 
all of them!). You will also need a modem and All that remains is to mention that the ball is now 
phone access. You'll also need a communications Squarely in your court! ... get on-line and GO 
package that will operate on yourcomputer. TO SMS Ah thee 


a 
Keghsf I can, as will the people at Pacific 
erat School on: (067) 618676, or 
Pacific Power's Community Relations at the 
following numbers: (02) 268 6800 OR (008) 451 
241. Hellen Phillips, Phil Farrell or Roger Buck 
Can assiSt you. 


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Term 3 - 1993 Information Transfer 


ymputer Education Group 





Review of Caddsman Cadet 
by Greig Tardiani 


(This is a Software Evaluation subbmitted to IT by a teacher who has used the proforma developed by the 
Computer Education Unit. The Evaluation is therefore done under headings that allow a thorough review. 
IT welcomes reviews in all formats - it is useful for other teachers to see how you rate a piece of software 
that they may be considering as a potential purchase. Ed.) 


Title Caddsman Cadet 
Computer(s) for which this software is available IBM Clone, DOS 2.1 or higher 
Topic area(s) Computer Aided Drawing 





Age group. LS, MS, US, A. 
Ability group All levels of secondary level 
_Date/lversion 1990, Version 2.12 
Auth Cadds Man Ltd 
Publisher Cadds Man Ltd 
Price $750 for 10 machines. $1 250 for a site license 
Recommended Retail $7 500 
_ Supplier Cadds Man Ltd or (Davron Daizo) 
Copyright, Licensing and availability details Single copy and site license available. 


Available in either 3.5" or 5.25" disks. 





Additional software required DOS 2.1 or higher. 


Required hardware computer 286 or higher, 386 recommended. 





Information Transfer Term 3- 1993 41 


New South Wales 





Memory 1 Meg of Ram 


Other Math co-processor essential. 
3 button mouse (all three are used) 


Optional hardware Digitiser pallet or Puck. 
Plotter printer for output. 
Contents of Package Three 3.5" compressed program disks. 


Three manuals: Reference manual, 
Programming language reference manual, and 
Reference manual update for version 2.12 





Level of Evaluation 
Screened [ X ] 
Full evaluation by subject specialist [ J 
Field tested [ X ] 
Evaluated by (full name) Greig Tardiani 
Date From 1990 to 1993 
Contact point Grantham High School 
Phone ( 02 ) 622 7300 
y r, r r 


The evaluator has been an Industrial Arts teacher for 14 years and computer co-ordinator for 3 years. The 
package has been extensively trialed with all ability levels in real life classroom situations. The test 
platforms were IBM 286 based computers with DOS 3.3 and 1 Meg of DRAM. 





Type of software 


Descripti 
Caddsman is a full function commercial 3D CAD program adapted with the help of well designed tutorial 
programs for educational use. The program has 999 layers, multiple pens, and full walk through facilities. 


EB iueational Obieniiv 
To expose student to an easy to use yet powerful CAD package that will expose them to the integration of 
computers into the areas of commercial Design and Drafting. 


Term 3 - 1993 Information Transfer 


omputer Education Group 


haces jataacsiae: | <te'¥ auth e bo bo dade ae oar at ree mE kane cr MI 6 MeN RAI AORN ee UN eS 


Individual, Small groups, Concept development, Class, Extension and Enrichment. 
EVALUATION SUMMARY 

Rating Scale: I - ImpressiveS - SatisfactoryU - Unsatisfactory 
Content Rating [1] S U 


The base program contains all the necessary drafting tools of a high-end 3 D CAD package. Icons replace 
menus, the program handles text well, and works with grid and co-ordinates for accurate drawing. The 
tutorial package that comes with the program is educationally based. An architectural package is also 
available. 


[I] S U 
All default values are pre-set allowing one to start drawing immediately. All three mouse buttons are used 
negating the need to use the keyboard. Unlike Autocad, you always work in 3D mode and can view from 
any angle the object being drawn. 


room Application Rati [I] S U 
Exceptionally good CAD package for introducing high level drawing to all levels of students. The program 
displays how professionals can draw on a computer. Designing of projects using the tools supplied allows 
the student to experiment with different sizes etc. and view the project from any angle before proceeding 
with manufacture. 


Support Material Rating [1] S U 

The South Australian Department of Education have developed tutorial modules specifically for 
Caddsman. Technical Schools of The Future (TSOF) have developed icon packs 

to replace the menus and tutorial packages aimed at making learning the general 

program enjoyable. General manuals are well written and easy to understand once 

the drawing terminology is understood. 


Recommendations 
I would highly recommend this package as it allows a true CAD package to be 
used within a school teaching environment that is understandable to students of 
any level. It also allows the advanced student to expand to high levels of the 
drawing fields. One detriment to the program is the need of a plotter if printing 
is to be of a reasonable speed, normal printers are very slow. 





Reference: 

NSW Department of Schools Education 
Services Directorate 

Computer Education Unit 

SOFTWARE EVALUATION FORM 


i? oe 





Information Transfer Term 3 - 1993 43 


Hp\(lierl Assn 


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Are you truly using the BEST 
Educational Computers 
in Your Classroom? 


COMPUTERS FOR The 


classroom isn’t an office, a 
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Z se ae hedae. <a ten adiates nanan tee 






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TAKE a closer look at the 
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Choose a computer for your 
DOES your classroom really las b i i ae 7 . a 
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‘ YOUreally should ask to : 
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See the Acorn range of 7/190 George Street, Parramatta, NSW 2155, 
educational computers. Phone: (02) 891 6555, Fax: (02) 635 9641 
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es COmputers for the Curriculum 


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