CRAYOLA-Sidewalk Crayons: Chalk. Brighter and bolder colors than ever before! Enhance your sidewalk drawing with Crayola's Sidewalk Crayons. These Sidewalk Crayons work in all Crayola Sidewalk Chalk Tools. This package contains fifteen fascinating colors. Conforms to ASTM D4236. Recommended for children ages 4 and up. WARNING: Choking Hazard-small parts. Not for children under 3 years. Imported.