Why wouldn't you go for a Lego Mindstorms kit? You could probably build a similar thing almost out of the box (BYO marker and whiteboard) and you can replace t

Why wouldn't you go for a Lego Mindstorms kit? You could probably build a similar thing almost out of the box (BYO marker and whiteboard) and you can replace the various parts with your own bits as you get more advanced. I suppose if you knew what you were doing going an Arduino is a cheaper option though.