Healthy Childrens Chalk: No dust, non-toxic, harmless to childrens respiratory system, absolutely safe for childrens entertainment.Durable and perfect for small hands: Nano-grade material, the same volume is 10-15 times more durable than ordinary chalk, sturdy and not easy to break. The size of each sidewalk chalk is perfect for childrens small hands, providing a comfortable grip for easy handling.Outdoor Chalk for Drawing Art Play: Our blackboard chalk is perfect for blackboards, sidewalks, backyards, driveways, playgrounds, brick walls, stones, etc. Whether it is childrens painting creation or teachers classroom teaching, it can be full of fun. It also helps improve childrens color recognition and color uniformity in hand-painting activities.WASHABLE AND EASY TO CLEAN: The water-soluble material makes the chalk easy to clean even when it is applied to clothes, which is easier to clean than crayons. You can help your child keep their hands clean by wiping with a damp cloth or sponge.