I have seen this activity on several different blogs and have always wanted to try it with Arin, but haven't in the past because I didn't want Arin to burn herself on the rocks. Uncle Todd was here yesterday, so Arin wanted to do some sort of a project with him. We had leftover rocks from when we had gatehered them for our tic-tac-toe game, so we decided to go ahead and try this activity. I put four rocks on a baking sheet and put them in the oven. I turned on the oven to 350 and let the rocks stay in there until the oven was preheated. Then, I took the rocks out of the oven and gave a couple to Arin and a couple to Uncle Todd. Then, they colored the rocks with crayons. The heat of the rocks melted the crayons, creating a cool effect. We were surprised though that the wax was so runny and I thought that the color would have been a bit more bold.
They also found out that it was cool to melt the crayon on the rock and then color with that crayon on paper, which created a different effect than coloring on paper with a cold crayon.