code.org - really cool site

Check out the exercise by Robomind where you use simple instructions to control your own robot.

http://www.code.org/educate

Here is a sample of a simple exercise that is used to test your skill : 

# Let the robot draw a square.

# Only use forward(3) and right.

# Use paintWhite for drawing

repeat(4)

{

i = 1

paintWhite 

repeatwhile(i<4) {

    forward

    paintWhite 

    i=i+1

}

j=1

paintWhite 

right

repeatwhile(j<4) {

    paintWhite 

    j=j+1

}

}

-->

Here is a workable solution. Maybe not the best solution but a real one at that.

There are many such fun exercises on the site.

Check it out.