If there was ever someone born to portray the true spirit of rock and roll, it is Jack Black. In this movie, that is what they needed, and that is just what he does.

Black plays Dewey Finn, a musician who doesn’t just live for rock. He barely acknowledges that there is anything else. Like the music he loves, Dewey is loud, immature, messy, self-absorbed, passionate, incapable of complying with any authority, rule, or attempt at civilization, and just about irresistable. Dewey’s love for the music is so pure and so complete that it is impossible for him to imagine that everyone might not support him.

That is why he is astonished when he is fired by his band and when his best friend Ned (screenwriter Mike White) tells him that if he does not start paying rent, he will have to move out. Ned was once a rocker with a group called Maggots of Death, but now he is a substitute teacher with a girlfriend and tells Dewey it is time to grow up.

So, when Dewey intercepts a call from Principal Mullins (Joan Cusack) offering Ned a substitute teacher position for fifth graders at a posh prep school, he accepts and shows up pretending to be Ned.

Of course he thinks he will just snooze through the classes and of course his students will be appalled (but also a little bit thrilled) by his sense of anarchy. When he tears down the neatly lettered class list of stars and demerits, they are stunned. They look around as though waiting for lightning to strike, a sort of ultimate demerit. But fifth graders are just young enough to trust their teacher and just old enough to be enthralled when he tells them that their secret new project will be to spend the entire school day creating a rock band. Once he assures them that this will impress the admissions office at Harvard, they are all on board.

Soon, everyone in the class is a part of the band, with guitar wizard Zach, back-up singers, roadies, groupies, and a stylist. The kids learn something about the history of rock, something about music, and quite a bit about expressing themselves. And Dewey learns something about what it really means to be part of a band.

This is by far the most accessible and conventional film from director Richard Linklater (Waking Life, Dazed and Confused) and White (Chuck and Buck and The Good Girl), neither of whom are known for heartwarming, feel-good movies. But that is what this is, a sort of To Sir With Love crossed with This is Spinal Tap. Black is enormously entertaining and the kids are terrific.

Parents should know that the movie includes some strong language, alcohol abuse, and drug references. A character loosens up when she gets tipsy. An unconscionable lie is portrayed as a creative solution to a problem. The overall theme of jettisoning schoolwork for rock and roll may also be a concern.

Families who see this movie should talk about how much Dewey loves rock and roll. Why is it so important to him? What does it allow him to express? What is the most important thing he learned from the kids, and what is the most important thing they learned from him?

Families who enjoy this movie will also enjoy The Commitments and This is Spinal Tap and they will enjoy Black’s performance as a devoted music fan in High Fidelity (all for mature audiences). For information about Black’s own rock band, Tenacious D, check here. Families might also like to see some very different movies about music teachers who touch the lives of students, like Music of the Heart and Mr. Holland’s Opus. And they might enjoy a very different story about a music teacher who begins by being a con man, The Music Man.