Nice sketch. However, we were hoping that the sketch would have shown some design evolution addressing some of the concerns we brought up in our comments to your group. For your presentation, be prepared to discuss the questions we have been asking you:

(From our previous comments) What is the role of tangibility in your system? What is the role of computation? How does it help the interaction and make it unique? Additionally, your system as presented will have a focus of user-user interactions in a collaborative task. How do you see your system supporting collaboration?