Here is a picture of our Foam Gnomes from last night:
Each one started out as about one-quarter inch of chemicals in the bottom of the plastic cup, along with a few drops of food coloring. We stirred like crazy with a popsicle stick, and then after a while the mixture changed color and started foaming. We used the popsicle stick to guide the foam straight up. It gave off a lot of heat! However, less than a minute after it stopped expanding, it was hard and you could pick it up and handle it, or add silly features to it.