The recipe for it came from one of my recent favorite blogs, We Made That and was quite easy to do. Just 8oz of glue, 8oz of water, 4oz of warm water, 1 tsp of borax. I laid off on the food color because I was a little concerned about staining hands. I dropped all the ingredients into the rotisserie tray as each child arrived and had them mix it themselves to see what it turned into.
GAK is a polymer, which means it is a long strain of molecules. I was describing it, but they were most interested in just playing with it. It effectively is silly putty.
One of the purchases I made this year which has gotten a lot of use, especially with all these sensory science experiments has been the long plastic spoons. The children felt a bit like mad scientists mixing it, and then use the spoon to play with it until they feel comfortable enough to pick it up with their hands. Some children will dive right in, especially with the gooey-ness, others like to warm up with the spoon.
This was another fun one where the moms got into playing with it like the children did. I gave out bags for the children/moms who wanted to take it home. We did, and I left it to the side and it creeped out of its ziplock bag, which was a bit creepy to find a glob of the gooey white stuff where I wasn’t quite expecting it!