You can take a little container of yogurt and mix it with Koolaid. It will make a colorful fingerpaint that won't taste as bad as the other fingerpaint does. :)
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For easy, safe fingerpaints, use whipped topping tinted with drink mix. They're safe even for babies to use (my son did this when he was in daycare and he wasn't 1 yet), but still messy enough to be appealing to small children.
