Color rocks with crayons. Place the rocks on a foil lined cookie sheet and bake them for 15 minutes at 200 degrees to melt the colors. Let them cool and then have the children grab an old sock, turn it inside out and let them rub the rock to polish it up and make it shine.
Crayon heart wall art - made this for my little girl, easy to make, just arrange in a heart and melt crayons with a blow dryer (there will be lots of splatter fyi).. add a picture in the middle to use it as a frame
Fill foil liners about two-thirds full with unwrapped crayon stubs in assorted colors, place in a muffin tin, and bake at 275 degrees until melted (about 10 minutes). Then freeze for cool colorers with zigzag edges.