Supplies:Borax (from the supermarket or a small box from laundromat)Elmer's Glue-All (White only)Food Coloring (optional)WaterOne large plastic jar w/screw lid - ala a large peanut butter jarOne plain old cupInstructions:Step "1"Add together;1/3 cup Elmer's Glue1/3 cup WaterFood coloringShake, stir or mix these ingredients until g ...view middle of the document...
... oh yeah, shake the jar tooShake until the slosh, slosh becomes thump, thumpOpen and remove the guk, you can scrap extra from the sidesNow play! It may stain things, could get stuck in carpets, who knows?The Science:Elmer's glue is copolymer polyvinylalcohol, PVA, a plastic made from oilBorax is a natural mineral mined from the earth made of boron, sodium, oxygen and water.When you add water to elmer's glue the PVA, being unstable, starts to dissolve in the water.When you add the wet borax, it is slightly acidic, and it reacts with the PVA to crosslink.This crosslinking causes the guk to undergo an irreversible gelation reaction much like when an egg boils to become a hard boiled egg. It is safe to handle, but hey! let's not eat it...OK?