Melting Crayons in the sun
My son is really into science experiments lately, so our latest one was if we could melt crayons by the heat from the sun. We used some older crayons and peeled the wrappers off, picked out some cookie cutters, and stuck the crayons inside. I laid them on a foil covered cookie sheet. This was a great success. The first day the one side was more melted than the other side, so we brainstormed hypothesis about why, concluding that there was more sun on that side. We also discovered that the fat crayons we had took longer to melt. These actually turned out great, and would make fun beginning of the year gifts for teachers.