Hubbard's Cupboard that was similar though, so maybe this story originated there.
Anyway, here's my version. I laminated a copy of my shape monster onto a large mailing envelope and cut out the mouth. I made shapes out of colored foam for the kids to feed the monster his lunch.
The text goes like this: "Shape Monster, Shape Monster Munch, Munch, Munch! I want to eat a ___________ for lunch!" The kids catch on quickly, and love stuffing shapes in his mouth. It's always a hit!
Isn't that monster cute? I have KPM Doodles to thank for that. If you'd like a copy of my Shape Monster Book, you can download it here.
P.S. Monsters are NOT just for Halloween!