1 c. Plaster Paris of Parrs, do not pack
Almost 1/2 c. cool water

Pour plastic into disposable container. Use a disposable stirring stick, stir in most of the water. Add 2-3 teaspoons liquid tempra paint, mixing well. Add a little more water as mixture thickens. Stir well and pour into containers. 3 ounce Dixie cups works well. Peel paper off when chalk is dry.