A pretty cool game for the week given. I didn't have someone else to play with so I played around with the controls and these are my thoughts on the game as a whole. The graphics could use some work, just being simple shapes. Something that makes sense given the amount of time you had. I also had some trouble with the controls, mainly the position of the keys. I generally play games with WASD controls. WSA being player one and DFG being player two doesn't make too much sense to me. WSA isn't very easy to control, in addition to DFG being too close to WSA. I just don't think that two people, both with hands, would be very comfortable squished up together trying to click the correct keys. Maybe use ASD and JKL or something of the like. Overall, after throwing what might be considered negative comments at you, I hope you know that I find the game to be pretty good. I just wanted to point out some things that I, personally, would like to see changed.
Edit: I just realized what you mean by the Makey Makey board. Now this whole thing makes much more sense. Great job!!