When a child mixes white school glue with liquid starch, the long polyvinyl acetate chains in the glue tangle around borate ions from the starch and form a stretchy net — the same cross-linking chemistry that makes slime peel off a table in one rubbery sheet instead of a sticky smear. - The Artful Age

I can remember the teachers in my kids’ preschool making slime! From a mixture of cornstarch and school glue. It’s safe, non toxic, and fun to play with. 

I made it at home to play with too. 

Well it turns out that there’s an interesting thing that happens in chemistry that makes this a kind of a unique substance - that has other uses. 

You can read the details of how it works here:

https://theartfulage.com/ap-when-a-child-mixes-white-school-glue-with-liquid-starch-the-long-polyvinyl-acetate-chains-in-the-glue-tangle-around-borate-ions-from-the-starch-and-form-a-stretchy-net-the-same-cross-linking-chemis/