The kids made hot rocks at 4-H project day and they are just so clever. There are kids in the club from 8th grade all the way down to preschoolers that come with their older siblings and all of them loved this project. The room was so quiet as they all made at least three of these rocks.
To make them, find some nice shaped rocks and give them a good bath. Lay the rocks out on a cookie sheet, heat the oven to 200 degrees and bake the rocks for 2 hours. When they are hot, and they will be very hot so use an oven mitt, set them on a piece of card board. Using crayons, draw on the rocks and the crayon will melt over the top of the rock. You can draw pictures or just let the colors run together. Here Dancer just pressed the crayon on the top of the rock and rock was hot enough that the crayon melted and ran down the sides. The next day, or when the rocks are totally and completely cool, buff the rocks with the soft cloth for a shiny finish. These probably will not hold up in the sun so we will be keeping them in the house.