This activity helps in developing pre-writing and writing skills. ,, the child receives more kinesthetic feedback when drawing or writing with a chalk. Having the child lay prone on the floor helps with proximal stability and assists in strengthening the shoulder muscles.
For this activity, you can have the child draw on a chalkboard or on the sidewalk.
While large chalks would work better on the sidewalk, try to use small (or even broken) chalk to promote a tripod grasp.