Do you remember playing with those sponge toys that would expand in water? Now you can introduce a new generation to the thrill of watching a toy absorb water. This tube of polymer beads are made to grow 100x their size in water. Simply fill a container with water, pour in as many beads as you want, then give it time to watch those little beads expand into shapes the size of marbles. You can use this as an experiment in water absorption, or a play time activity. Once the beads expand, children can play with them as marbles, or you can throw them in the garden to let them gradually fill the soil with water.