You even (probably) have all the ingredients in your kitchen already:
1 Cup Flour
1/2 Cup Salt
2 T Cream of Tarter
2 T Cooking Oil
1 Cup Water
Mix together flour, salt, cream of tarter, oil and water in a sauce pan. Add food coloring. This is a good opportunity for little ones to do some experimenting with colors and learn how to mix them to create the colors they like. (But if they're really little they may just want to dump in a bit of every color, which makes brown. We've had quite a lot of brown play-dough. That's ok, just shape it into "logs" and build log cabins!)
Heat over low heat and stir frequently. It will get really sticky and not seem like it's working right. DO NOT throw the whole pan in the sink and stomp out of the kitchen. (Not that anyone has ever done that...)
After a few minutes it will get better! Just continue heating and stirring until it gets the right texture and you can form a ball with it. Remove from pan, remember to let it cool a bit before the kids touch it, then it's ready to go!
Thanks for the recipe Grandma Jan! We are so blessed to have you!