I have seen these little puzzle pieces around but never thought much of them until I stumbled across this site. It is amazing what can be done with these simple little shapes that can be made out of paper. check out some of the stories she has created. It is quite interesting and makes a good math/art tie in.
http://www.geocities.com/tangramfan/
Shar ARndT
Live life out of your imagination not your history.