Muppet fans know that some characters evolve while others just spring up from out of nowhere. Cookie Monster, for example, began life as somewhat more ferocious-looking monster (the row of sharp teeth helped) in several commercials before being toned down and brought to Sesame Street.

In the clip below, a pre-Sesame Street Cookie Monster devours a machine while the machine describes how it works and what its many functions are. Actually, it only has one main function, but you'll have to watch the clip for that.

High on the list of things none of you probably care about is the fact that Grover is my favorite Muppet of all time. He and I even share a birthday (it's true). What I love about Grover, besides his lovable furriness, is how willing he is to do himself bodily harm in the name of education. After the jump I've placed five clips of Grover doing what he does best: teaching kids no matter how much physical punishment it causes him. Now let's all learn together, shall we?