If I had a pool I would totally try this out. Put a glow stick in a balloon for pool lanterns. Pool party on a Summer night! I think this could work pinned up on the fence of a backyard without a pool, too, so really great idea for any outdoor BBQ/party!
I like the idea of students creating a personal budget. Second graders learn how to add and subtract money, and this project would be great for them to engage in. They could work on creating a budget that would help them save for a desired item.