1 Tbs white vinegar
2 Tbs baking soda
1 Tbs cornstarch
1/4 Tbs glycerine

Recycled egg carton
Natural food-based dyes

Mix vinegar and baking soda together in a small bowl.  Expect a bit of foaming!  When the mixture stops foaming, add remaining ingredients.  Pour a small amount of mixture into each of the cups in the egg carton.  Add several drops of food coloring to each carton cup, making a new color in each cup. Add more than you think you need, the color will lighten as it dries.  Stir until the color is well-mixed.  Set the egg carton aside and allow mixture to harden overnight. 

Happy Painting!

Photo by sallylondon

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