Chemistry Experiment, Need Help o,o Best Answer 10 Points !?

Well borax is either sodium borate, sodium tetraborate, or disodium tetraborate now when borax reacts with the polyvinyl alcohol is the glue resulting in cross linking of polyvinyl alcohol with borax. This makes it into a non newtonian fluid (similar to quick sand). The cornstarch and water add bulk to the cross linked polymer and increase the density of your system so that you can make a quasi solid out of it. This is what results in the formation of your bouncy ball.