Bands rarely earn encores anymore. A concert’s rules, not its mojo, oblige groups to return for one last song, even if the preceding 90-minute set sounded no better than the cries of a dying cat.

School of Rock earns every laugh and, yes, bit of tear it draws from you. It looks like it would be the same old gooey candy about a shifty guy whose heart is warmed to a new world view by a bunch of cute-cute kids. But star Jack Black, co-star / writer Mike White and director Richard Linklater subversively smear that candy all over their face.

The movie is a triumph, riotously funny, moving and deftly mainstream without falling into clichéd pitfalls. It’s obvious material made surprising by smart filmmaking choices. And if this movie doesn’t make Black a household name, then, well, nothing will.

He plays Dewey Finn, a rock musician who is good at going over the top on solos, but not at paying the rent or getting on with his band mates. Dewey is mooching a place to stay off his best friend Ned (White), a substitute teacher whom Dewey owes at least $2,000 in back rent money.

Fired from his band, Dewey takes a call about a job for Ned, fakes his voice and fraudulently signs on to teach fourth grade at a prestigious private school. At first bored and annoyed, Dewey is inspired when he hears the children play in their classical music class. Deciding to teach them in the ways of rock ‘n’ roll, he hatches a plan to win a $20,000 battle of the bands using the kids.

School of Rock captures the wonderful allure of rock ‘n’ roll as well, if not better than, Almost Famous. It’s on the kids’ faces as they listen to “homework assignments” such as Led Zeppelin and Yes and when they walk in and behold the expanse of the climactic concert venue.

And Black, best known in musical circles as one-half of spoof-rockers Tenacious D, subtly finds that Dewey has lost touch with rock as well. The way he helps the kids, as they help him, is never sentimental and always true.

Larger than life in every scene, it’s Black’s movie all the way, but he never overdoes it. He remembers not to crowd out the kids and leaves room for fantastic supporting work from Joan Cusack, who turns what you’d expect to be a disapproving principal into a character with surprising depth.

School of Rock is one outstanding comic set piece after another, book-ended with sweetness and an impeccable rock soundtrack. It’s a joyous film, and one of the best of the year.