Sidewalk Chalk
["2 Tbsp. liquid tempera paints", "1/4 c. water", "1/2 c. plaster of Paris"]
["Combine paint and water in a container.", "Slowly stir in the plaster of Paris.", "Pour into waxed paper cups, plastic cups (grease with vegetable oil) or candle molds.", "Remove chalk when hard (about 3 hours), then allow it to dry for 4 days."]
["liquid tempera paints", "water", "plaster"]