Corn starch clay hardens to a nice, smooth surface that's wonderful for children's art projects. Leave the mixture white and paint your project after the clay dries, or add food coloring or a dye to tint the clay any color you like. Expect projects to harden in one to four days, or speed the process by using the oven. Keep leftover clay up to two weeks in a sealed container with a piece of damp sponge.
Mix water and salt in a large pan while cooking over medium heat.
Mix in the corn starch gradually and heat until the mixture thickens into a mass of clay.
Remove from pan and set aside to cool on a sheet of freezer paper. Cover with a damp cloth.
Knead the clay like bread dough once it is cool. Add a few drops of food coloring to dye the clay at this stage if you like. If the clay is sticky, dust your hands and the work surface with a little extra corn starch.
Do not allow children to cook the mixture or handle the clay when hot.