This is the best idea by far that I have gotten off Pinterest!!
My children become bored with new things and even more bored with practical play toys. (this is why we don't blow our money on expensive action figures) So I try my best to come up with clever inexpensive ideas to keep them occupied....even if they are a little messy, because having boys means the messier the better!
Seems food coloring + water + cornstarch = loads of fun!!
Just take all 3 ingredients, a little at a time, (no measuring here) keep it in a liquefied state.....too much cornstarch will give you Gak.
Throw in a few paint brushes
and watch the artistic creations begin;