My teaching partner does all the math, but we do a huge party for pi day every year.
1. She dresses up like a PIE.
2. We have about 20 room moms come in to volunteers, and the kids bring in pies
3. They graph pie preferences, and then they have to divide the pies into portions equal to the number of children that want that kind of pie (for example, if only 4 kids want a pie, they each get 1/4 of the pie, where the more popular pies, each kids gets about 1/32 of the pie)
4. then, while we eat, we read to them from pictures books: Sir Cumference and the Knights of the Round table, Sir Cumference and the Sword in the Stone, Sir Cumference and the Lady Di Ameter, etc...)
Fun day...love it!