my co-teacher is doing a math project with her class right now. In groups, the kids come up with a theme for a store to sell items. They bring in paper ads and cut out items for a store, and give each item a price. Then, they have to decide to have a sale in their store, and determine a percentage that will be taken off of each item (and it can't be something easy!). For a Language Arts connection, they have to create an advertisement for the store (either print or television commercial). They're going to use paper money and write checks to "buy" items.
The kids really seem to like it, and I'm sure that there's a lot more that they could do with it, even designing the layout of the store to fit the geometry in
