1 c. Plaster of Paris (do not pack)
Almost 1/2 c. cool water

Pour plaster into a disposable container (butter container or large paper cup). Using a disposable stirring stick, stir in most of water. Add 2-3 tablespoons of liquid tempera, mixing well, especially at bottom. Add a little more water as mixture thickens. Stir well and pour into containers. Three oz. Dixie cups work well. Peel paper off when chalk is dry. Have fun!