Borax, an ingredient in liquid starch, combines with glue for a chemical reaction that polymerizes — links together — the sticky chains of glue molecules. (Picture adding a handful of magnets to a bucket of paper-clip chains.) A classic putty.
Once you've made it, play with it: Let your child pull
it into a web or rope with her fingers, or give her a cup and have her stretch the Flubber over its
top, then drop marbles or coins onto the stretched surface and see what happens.
In a large bowl, stir together the glue with the liquid starch until the mixture comes together in a wet clump.
Turn mixture out onto the counter and knead until smooth, 10 to 15 minutes (you'll need to pat your hands and the counter dry a few times as you do this).
1/2 cup of Elmer's white glue
1/2 cup of liquid starch (get this in the laundry aisle)