In Richard Linklater's "School of Rock," Jack Black gives the best performance by an actor I didn't care if I ever saw again.

Black ("Shallow Hal") has an obnoxious screen presence. His cocky attitude, noise level and schlumpy physique - often cloaked only in a pair of Jockeys - are a general assault on the senses.

But "School of Rock" may be to Black what "The Nutty Professor" was to Jerry Lewis, or "Groundhog Day" was to Bill Murray - that rare, perfectly tailored opportunity to play against one's broadest impulses. Not to neutralize them, necessarily, but to tame them and turn them into something very human and charming.

In the first few minutes of "School of Rock," in which Black's Dewey Finn is introduced as a delusional, loudmouthed slacker who sees himself as the next Keith Moon while sponging off his friends, you'll want to claw your way to the aisle and make a run for it.

But stick around. It doesn't get better; it gets wonderful. And forget the PG-13 rating - this is fun for everyone, even those (like me) who hate contemporary rock music.

"School of Rock," like the current gospel comedy "The Fighting Temptations," offers a new spin on the old let's-put-on-a-show routine.

Dewey has just been thrown out of his own band and is about to be evicted by his roommate, Ned Schneebly (Mike White). He assumes Ned's identity as a temp teacher and takes a job at a rigid private elementary school.

It's a tough gig, since Dewey doesn't know anything that would interest or advance the education of a fourth-grader. But he has to do something to pass the time, and hits on the idea of turning his class into a rock group and entering an upcoming "battle of the bands."

The tension, what there is of it, arises from whether they can get to the contest before Dewey's deception is discovered by the kids, his roommate or the school's riotously uptight principal (Joan Cusack).

Besides playing Dewey's roommate with a loyalty that could destroy his love life, White wrote the screenplay with Black's "Animal House" slobness in mind, and served it up to his friend like a hanging curve to Barry Bonds. You won't see a more dominant comedy performance this year.

Or, at the same time, more generous. Black, like Dewey, lets the kids shine, and together, they do indeed put on a show, and one you won't want to see end.

Without sentimentalizing them, the movie is full of useful messages: for the kids, who learn the value of teamwork (albeit in a sneaky cause); for the closet-rocker principal, who learns to balance discipline and play, and for parents, who see what their children are capable of when encouraged and motivated.

But the best lessons are reserved for Dewey, who finally finds a way out of his blinding self-absorption and discovers that he may have been born to a higher calling than hammering on a bass guitar and diving into a crowd at a rock concert.

And that he can answer the call without giving those things up.