I think the brand of cornstarch and humidity may have a lot to do with the variance in cornstarch amounts from what I've observed in my experiments.
The recipe worked great when I tried it a couple times with just 1/4 cup cornstarch, but a co-worker found that he needed 2 1/4 cups to get the dough-like consistency of a good fluffy slime. If you find that your slime is still sticky after kneading it for a while, keep adding cornstarch to the slime and knead it in until you get a good consistency. Slowly add 5 more tablespoons of water, stirring well after each one.
To make the slime, you'll need shampoo of any type - though the thicker, the better - and cornstarch.
