What you need:
- glycerin blocks (available at craft stores)
- food coloring
- shaped ice-cube trays (we like the rubber kind)
What to do:
- Melt the glycerin according to the package directions.
- Divide glycerin into a few different bowls and stir in the food colorings of your choice.
- Pour glycerin into ice-cube trays and allow to cool according to directions on package.