Play-Doh

Play-Doh is a modelling clay sold as a children's toy.

History
While Homer was gaining weight to try to get himself put onto disability for obesity, he ate all the food in the house. Maggie offered him a donut out of Play-Doh, and when Bart pointed out that it was non-toxic, Homer heartily ate the Play-Doh donut.

During free time at school, Ralph put some Play-Doh in his mouth. He then squeezed it in different shapes out through his nose and ears.

Non-canon
After the Simpsons brought the Golem home and got him to speak, they learned that he was lonely. Marge and Lisa made him a wife out of Play-Doh.

Behind the Laughter

 * Worth noting: In real life, Play-Doh is non-toxic, but it's not recommended for eating.
 * When Ralph squeeezes the Play-Doh out through his nose and ears, he resembles the "Fun Factory", a real-life Play-Doh toy.