Bart Simpson

In the "Jazzy and the Pussycats" episode of animated Fox sitcom [The Simpsons], Bart is encouraged to play drums to channel his anger and keep him out of mischief. He excels and plays with his sister Lisa's group, and then is recruited by real local jazzbos Defonzo "Skinny" Palmer and Marcus "Marbles" Le Marquez to play with them.

A lot of other jazz musicians get a quick mention at a benefit concert:

Krusty the Clown: Hey hey! We got more jazz superstars on the way, folks! Gooey Martin, Willie Mims, Dropjaws Turner, Sketch Friendly, Tootsie Childs, Sammy Biltmore, No-Talent Jones, Anwar Bernitez, Bossy Marmalade, Bad-Check Mazursky, Ray-Ray Takamura, Shakey Premise, Bootsy Crouton, Richard Sakai, The Premarital Sextet, C.S.I. Miami, D.W. Jitters, The Chubb Group, Canteloupe St. Pierre and many many more funny names.

Bart was previously in The Party Posse and in the future will be in Captain Bart and the Tequila Mockingbirds.

He also cut a novelty song (a parody of MC Hammer's "Can't Touch This," apparently produced BY MMC Hammer) when he was briefly popular as the "I didn't do it boy" when he appeared on The Krusty the Klown Show. That's the "Bart Gets Famous" episode (February 3, 1994).