Crayon Label Remover
A simple tool to cut labels off of crayons. Works at least on Playskool and Crayola - Crayolas are a little tight because their crayons are a bit thicker. The razor blade is entirely contained within the enclosure, though obviously if your child's fingers are smaller than a crayon, maybe don't let them use this.
The actual cutting only uses half the blade, so if they get dull, open it up and flip them around.
Hardware Required:
2x #9 razor blades
4x M3x10 screws