"The School of Rock" is sort of a mess. But it could have been — and probably should have been — a much bigger mess.

Among other things, this music-based comedy borrows from such diverse cinematic sources as "Dead Poet's Society," "Fame," "The Bad News Bears" and "Catch Me If You Can." And star Jack Black, a comedian who usually makes the movies he appears in entertaining but has the bad habit of hijacking some of them . . . to their detriment. (The major exception being "High Fidelity.")

Yet, for some reason, it works. Hilariously.

"The School of Rock" is also one of the sweetest, most appealing comedies to come along in quite some time, and much of that can be attributed to Black, who reveals a considerably more tender side here. (This is also one of the cleanest PG-13 rated films in recent memory, aside from a few tame profanities and some drug imagery.)

Black stars as Dewey Finn, a failed rock musician who needs a job. He's just been thrown out of his band, and he's in danger of being kicked out of his apartment unless he gets some fast cash.

So he decides to impersonate his roommate, Ned (Mike White, who also wrote the film), a substitute teacher. Dewey accepts a position at Horace Green, a first-rate prep school run by rigid principal Rosalie Mullins (Joan Cusack).

True, Dewey has no experience, but he figures he can simply "baby-sit" the kids and slack off for a few weeks, while collecting a paycheck. But then something unexpected happens; he discovers his students are musical prodigies and may be able to provide the perfect back-up band for the rock group of his dreams and win an upcoming Battle of the Bands.

Director Richard Linklater selected the youngsters here for their musical, rather than acting, abilities. And as amazing as they are (especially Joey Gaydos Jr.'s guitar-shredding skills), their most impressive talent may be keeping a straight face when Black cuts loose with goofy facial and body contortions.

Obviously, this is Black's show. And longtime fans won't be disappointed. He's just as wild as ever. However, there's a real vulnerability to his performance that hasn't really been onscreen before.

Cusack again impresses in what's a rather underwritten role. (The scenes in which her character finally cuts loose are among the film's best.)

"The School of Rock" is rated PG-13 for a handful of profanities, some mildly vulgar humor (references), drug references and some slapstick violence (stage diving). Running time: 108 minutes.

---

E-MAIL: jeff@desnews.com