We dyed rice last week and it has been the best toy!
I threw about a 1/2 cup of rice in a plastic container and added a few drops of rubbing alcohol and a few drops of food coloring and shook it up. Then I laid it out on a cookie sheet for about 1/2 hour until it dried.
I found quite a few recipes for this online but using the rubbing alcohol worked the best.
I lay a plastic tablecloth on the floor and supplied the cups, scoops and spoons and Yahoo went at it.
Rainbow Rice kept her busy for an hour!
The only problem with Rainbow Rice is the fact that Yip, Yap and Yahoo don't like to share and my rice supply is running low. It's not often I can find something that all three of my kids like to play with.