1. Poul Henriksen Computing Laboratory University of Kent
greenfoot
Poul Henriksen
Computing Laboratory
University of Kent

2. greenfoot A microworld meta-framework Animated execution
Flexible scenarios
Animated execution
Direct interaction
IDE (with editor, debugger, etc)
Aimed at high school level and CS1
Microworlds:
Karel, Marine Biology Case study, turtle graphics
First BlueJ Day, Houston, Texas, 1st March 2006

3. Demo

4. Decoupled scenarios
Scenarios are decoupled from the animation framework
This leads to
easier scenario development
more scenarios
individual scenarios (for specific target groups)
First BlueJ Day, Houston, Texas, 1st March 2006

5. implement framework (with fixed scenario)
Roles
Microworlds
Greenfoot
implement framework (with fixed scenario)
implement framework
framework implementor
framework implementor
design scenario
design exercise
teacher
teacher
Can let the keen students create their own scenarios.
design exercise
student
solve exercise
student
solve exercise
First BlueJ Day, Houston, Texas, 1st March 2006

6. The teacher Teachers choose / write / share scenarios
Typical scenario:
Wombats: 3 classes, 266 lines in total
TurtleGraphics: 6 classes, 276 lines total
Ants: 6 classes, 598 lines in total
Bricks: 4 classes, 303 lines in total
Flexibility in choice of context
First BlueJ Day, Houston, Texas, 1st March 2006

7. The student public class CircleTurtle extends Turtle {
public CircleTurtle()
penDown(); }
public void act()
move(5);
turn(2);
Initially the student can get away with interaction with the objects: invoking methods, observing behaviour.
The code the student woks with can be VERY simple but still do some interesting stuff - visually.
First BlueJ Day, Houston, Texas, 1st March 2006

8. Summary aimed at high school level and CS1
engaging – generate interest
visual
flexible
teacher support
migration to other IDEs (BlueJ!)
First BlueJ Day, Houston, Texas, 1st March 2006

9. Status Prototype available: www.greenfoot.org Distribution: free
Timeline:
1.0 release later this year
First BlueJ Day, Houston, Texas, 1st March 2006