This is amazing! Take about a Tablespoon of the tiny colorful pellets and place them in a bowl of water. A few hours later they have expanded to over 2 cups of colorful transparent gel like marbles! Then the real fun starts as you bounce, roll, or just run your fingers through the slippery spheres. Includes a reusable plastic test tube and instructions. includes experiments and the science of these expanding polymers. For ages 4 and up with adult supervision.