Crayon Crafts from MommyCracked.net - Unwrap and break the crayons into pieces, placing in a muffin tin. Bake in oven preheated to 150 degrees for 20 minutes. May need more or less time depending on mold size. After removing from the oven, place the tin in the freezer until crayons harden. It took our batch about 15-20 minutes. Once hardened, the crayons will easily pop out, but be forewarned…they are very delicate and may crack easily.