Elmo's World/Letter/Not a Letter (by They Might Be Giants)

Cast

 * Tortoise, Hare, Seagull, Beachball and Football as They Might Be Giants

Lyrics
Tortoise: What's that? That is a letter. What is that? Hare: That's not a letter. That's a letter. That's not a letter. Seagull: That is a letter. Is that a letter? I don't know what that is. Beachball: That's so a letter. What is that? Whatever it is, that's not a letter. Football: That's a letter. Is that a letter, or what? That's a letter. Only it's upside down.