Characters sometimes learn lessons about topics like friendship and responsibility, but in general the show is intended to entertain and amuse rather than convey specific positive messages. Potty humor includes body odor and farting.
Some pranks and pratfalls (a man leaps over the edge of a ship to get away from teens he dislikes, for example), but there's no mistaking that they're strictly for laughs.
Teens have crushes on each other, but everything's pretty innocent, with just the occasional kiss or two. Zack in particular makes a fair number of comments regarding girls' attractiveness (i.e. "I'm going to study anatomy, starting with her"). Zack briefly shares a room with a girl, but nothing happens.