With adult supervision, mix 1/4 cup white school glue with 1/4 cup water in a Styrofoam cup. Use a craft stick to mix, adding a couple drops of food coloring for fun.
This is where the adult supervision comes in. On the stove, using a sauce pan, heat 1-1/4 cups water just until steam starts to rise. Mix in 1/8 cups Borax (20 Mule Team Borax) and stir until dissolved. Pour the solution into a storage container that has a tight lid. Immediately wash the sauce pan.
Pour 1/3 cup of the Borax solution into the glue/water mixture and stir with the craft stick.
Over the sink, remove the glob and pour off the remaining liquid. Knead the glob with your hands. How does it feel? Can it stretch? Pinch off a little bit and roll into a ball. Can it bounce on the kitchen table?
Why does the Gak stretch, even though the glue and Borax can't? The glue/water, when mixed with the Borax caused a chemical reaction, resulting in a new material that is different than the original materials. In this case, you created a polymer. "Poly" means many and "mer" means parts. A polymer is a chain of many molecules strung together, creating usually stretchy or bouncy materials. Some of the common polymers around the house are nylon stockings, plastic soda bottles, plastic sandwich bags and balloons.
The perfect storage container for GAK is a disposable Gladware container.
