If you have ever made play dough for your kids that turns into a salt block, you should try this recipe. Jaxon loves play dough, so I make this quite a bit! You really should keep it in your fridge, because I think it can mold after time if you don't.
Mix together:
1 c. flour
1/4 c. salt
2 T. cream of tartar
Add:
1 T. vegetable oil
1 c. water
Put this in a pan on medium heat, stir for 5-7 minutes, or until it gets playdough like consistency. Then add your food coloring, and enjoy!