"Tell a Joke" is a Sesame Street song sung by Harvey Kneeslapper. Luis is feeling glum, Susan is feeling a bit tired, and Bob is feeling terrific. However, Bob informs them that they'll all feel worse in a moment, because Harvey is coming by, wanting to tell them a great joke. Susan says they aren't in the mood for jokes, which Harvey says is the best time to tell them. He sings about how telling jokes always cheers him up when he's sad, angry, or scared. During the song, he tells a number of terrible jokes, which make the others leave one by one before the song is finished.