By adding a very small amount of water to gelatin, kids can create a simple plastic that hardens into colorful window decorations. Gelatin is formed from collagen, a protein made of tiny fibers that's essential for keeping cells stuck together. As the water evaporates, it leaves behind a product that is lightweight and strong but without any of the oil-based chemicals used in many factory-made plastics. The bonus: It glimmers and shimmers in the sun.
Boil 3 tablespoons of the water and pour it into the measuring cup. Add 1 envelope of gelatin and a few drops of food coloring. Stir the mixture slowly until it's combined. Let it sit for about a minute, then stir it again to minimize air bubbles.
Pour the mixture onto a plastic plate. If you like, sprinkle glitter on top of the gelatin, or add one or two drops of different-colored food coloring and swirl with a toothpick to make a marbled pattern.
Repeat steps 1 and 2 with the remaining envelopes of gelatin, varying the shades of food coloring each time.
Let the gelatins dry until hardened, at least overnight. Peel them off the plates, then cut them into shapes with scissors. Using a hole punch, make holes at the top of them.
If your light catchers start to curl, wrap them in a sheet of parchment paper, then place them between two heavy books. When they're flat, use markers to draw on them, if you like.
Suspend each from a string, ribbon, or fishing line and hang in a sunny window.