Kojo is a graphical learning environment aimed at teaching children and curious adults computer programming and geometry through a Scala DSL. It utilizes turtle graphics to help users enter commands that control movements and drawing. The platform encourages functional programming and provides resources for further learning.

1. Kojo Chicago Area Scala Enthusiasts April 15, 2010

2. What is Kojo? Kojo is a graphical learning environment for children (and curious adults). Teaches computer programming and geometry Built on the NetBeans platform Uses concepts from Logo and Processing Uses a Scala DSL as its teaching language!

3. Screenshot

4. Turtle Graphics Kojo uses the "turtle graphics" metaphor to explain programming and geometric concepts. The student enters commands in the script editor window, and the "turtle" follows the commands. Most commands relate to movement and drawing

5. Sample Commands forward(n) - move turtle forward n pixels left - turn turtle left 90º left(n) - turn turtle left n degrees right(n) - turn turtle right n degrees penDown - have the turtle draw a line as it moves penUp - have turtle move without drawing a line setPenColor(color) - change pen to color setPenThickness(n) - change pen width to n pixels setFillColor(color) - fill in concave shapes with color clear - erase the canvas

6. Draw a square forward (100) right forward (100) right forward (100) right forward (100) // tedious!

7. But Kojo is Scala! val sides = 4 val length = 100 (1 to sides) foreach { forward(length) right } // much better! // get them hooked on DRY when they're // still young!

8. Functional programming def tree(distance: Double) { if (distance > 4) { setPenThickness(distance/7) forward(distance) right(25) tree(distance*0.8-2) left(45) tree(distance-10) right(20) back(distance) } } clear tree(90)

9. Result

10. Resources http://www.kogics.net/sf:kojo http://kojoenv.wordpress.com/

11. Interactivity