Well, he knew what illicit and incriminating meant...if not sociopath and hermaphrodite. Wait, he probably knows those words from all of his expulsions.
I do think he's smart, though. He's as smart or smarter than Gary, but lacks Gary's cunning and persuasiveness. And being a punk who beats up people doesn't help his reputation. But the teachers think Jimmy is smart, and he's pretty good at PR, so, yeah. He's smart.