We have all played with these wonderful substances as kids. Here is the science behind them and how to make your own at home.
Silly Putty - Here is a little instructional on making this super substance. I remember countless hours using this to make everything from a fake nose to picking up cartoons in the Sunday paper.
Play-doh - Another kid favorite! There are a few ways to make this, both cooking and non cooking methods are described.
Moonsand - This product is relatively new on the market and is a little pricey. Here is a little tutorial on making this fun filled toy on the cheap.