One of the last Cartoon Network series during Jim Samples' tenure as head honcho at the network, you'd be hard pressed to find Class of 3000 on their website today. Seems the current administration wants nothing to do with it. Their loss.
This flash animated series was set in CN's hometown of Atlanta, and is built around jazzman Sonny Bridges (Andre "3000" Benjamin of Outkast, who co-created the series and served as executive producer), who is coaxed out of retirement by a young fan and become music teacher at an exclusive school in the city. In short, this was an inner-city answer to the Jack Black hit, "School of Rock", which, coincidentally, has aired on CN as a favor to sister network TBS, regardless of what anyone thinks to the contrary. Andre could've actually used Black's help with this show, considering how CN gave up on it after just 28 episodes were produced. The series was officially cancelled in 2008.
Here's a sample clip:
Seeing as how this was an independently produced series commissioned by CN, one wonders if/when it'll turn up again.