There is a section in my recipe box titled "Misc." There are several rather wacky family recipes (or science experiments) and Maggie is a great age to start trying them. Maggie's playdough was dried out when we went to use it today, so we whipped up some of my mom's recipe. She picked two colors (blue and white) and I made 1/4 batch, or about 3/4 cup of each.
2 c. flour
1 c. salt
4 t. cream of tartar.
Combine in a saucepan. Add 2 c. colored water and 4 t. oil. Stir quickly and cook over medium heat. Stir constantly until it forms a ball. Turn out and knead. cool. Store at room temperature in Tupperware.
I made 1/4 batch at a time because you add the color when you first mix it, not afterward. It was fast and easy, only about 5 minutes per batch.