Materials: crayons (we used ones that were dull or already broken)
exacto knife (optional)
Step 1: Peel all the paper off of the crayons. This is where the exacto knife comes into play; it's a lot easier to take off the paper if you cut a line in the paper first.
Step 2: Break the crayons into small pieces, about an inch or so. Arrange the colors in the muffin tin however you'd like (we grouped similar colors, but didn't use more than one of the same colored crayon because the boys wanted theirs to be "rainbow").
Some of our crayons cracked a little, but the boys loved it, and even the baby (15 months old) got in on the action. They were much easier for the baby to grip than the regular skinny crayons, and the older boys thought it was neat that the same crayon produced different colors.