ddsz

1. Powerful Ideas
Constructivist Educational
Techniques in Computer
Programming Using MSWLogo©
Copyright 2002, Tony Gauvin, UMFK

2. Introduction
 Tony Gauvin, Assistant Professor of E-
Commerce, UMFK
 Developed an Interest in MSWLogo as a tool
for exploration of advanced Computer
Science Topics while a Graduate Student at
UM
 Based on Draft copy of Discrete Logo written
by Dr. George Markowsky, Chair, Computer
Science Department, UM

3. What Is Logo?
 Logo is both an educational Philosophy and a
programming language based on
Constructivism
 Constructivism views knowledge as being
created by learners in their own minds
through interaction with other people and the
world around them.
 This theory is most closely associated with
Jean Piaget, the Swiss psychologist, who
spent decades studying and documenting the
learning processes of young children.

4. A Brief History of Logo
 Seymour Papert and Marvin Minsky
co-founded MIT’s Artificial
Intelligence Lab in mid ’60s
 Papert and others developed the
Logo programming language in 1967
 In 1980 Papert published
Mindstorms

5. Logo Basics
 Turtle(s) moving in a world controlled by
the user
 Turtle(s) act on and react to the World
controlled by the User
 The only data structure is a list (LISP
heritage)
 Commands are simple and intuitive
 “low threshold and NO ceiling”

6. LOGO Today
 STARLogo
 Massively Parallel
 Developed by Mitchel Resnick at MIT
 Turtles, Termites, and Traffic Jams:
Explorations in Massively Parallel Microworlds
 UCBLogo
 Unix, msDos, Mac
 Brian Harvey at UC at Berkeley
 Computer Science Logo Style

7. LOGO Today
 MSWLogo
 Windows (GUI) version of UCBLogo
 George Mills at Softronics, INC
 Has all the power of any windows
programming Language
 Great tool for exploring Advanced
Computer Topics

8. Today’s Topic
 Teaching programming concepts using
MSWLogo
 Two goals
 Use Iteration in Geometric Constructions
 Use Recursion In Geometric Constructions

Fractals
 Methods of Instruction
 The student experience is Totally Hands On
 By using Constructivism Educational Philosophy

9. MSWLogo Primer

10. Turtle commands
 To move
 Forward (# of steps) FD
 Back (# of steps) BK
 Home (back to the Middle)
 To Turn
 Right (# of Degrees) RT
 Left (# of Degrees) LT
 Pen Commands
 PenUp PU
 PenDown PD
 SetPenColor [Red, Green, Blue] O-255

11. MSWLogo Commands
 Edit <procedure>

Creates a procedure (program)
 Edall

Edit all procedures in memory
 ClearScreen CS
 Repeat # [stuff to do]
 :<Identifier>

Variable (place to store stuff .. Memory)
 Mathematics

*, +, -, /

(4 +3)/12*3-6

12. Draw a square
 Lets make the turtle draw a square
 First think how you would draw a square.
 Then tell the turtle to do it
 FD 100 RT 90
 FD 100 RT 90
 FD 100 RT 90
 FD 100 RT 90
 Repeat 4 [FD 100 RT 90]

13. Create a program for Drawing
a square
 Invoke the editor by typing “edall”
 Every procedure
To <name> <maybe some stuff>
<stuff to do>
End
 Remember variables can be used (:X)

14. The square program
To square : size
Repeat 4 [fd :size rt 90]
END
Type run square #

15. Something Cool
 What if the turtle took a step and turned
slightly and drew another Square?
 And then did this a bunch of times??
 To cool :size
Repeat 100 [square :size fd 1 rt 10]
END

16. Something Cool

17. Drawing a fern
 A fern is a Fractal
 Structure is repeated
 Every leaf is a fern
 Structure is recursive

18. MSWLogo Fern
 A Fern is
 A stem
 A fern to the left
 A fern to the right
 A fern to the front

19. Program for Drawing a Fern
 Teaching a turtle Botany
 Fern program
 Go forward
 Draw a fern to the left
 Go back
 Draw a fern to the right
 Go Back
 Draw a fern to the front
 Go Back
 Till it gets too small to draw

20. The program
to fern :size
if :size < 4 [stop]
fd :size / 25
lt 90 fern :size * .3
rt 90
rt 90 fern :size * .3
lt 90 fern :size * .85
bk :size / 25
end

21. A Cool Fractal Fern

22. What we learned
 Programming using Iteration
 Turtle drawing Square
 Programming using recursion
 Turtle drawing Fractals
 Programming is fun AND creative

23. Logo Resources
 MSWLogo
 http://www.softronix.com/logo.html
 Logo Foundation
 http://el.www.media.mit.edu/groups/logo-
foundation/
 Logo Art Gallery
 http://www.geocities.com/CollegePark/Lab/2276/
 Beginnings of My Logo workshop
 http://littleblack.umfk.maine.edu

24. Questions??