It always makes me feel a little silly to be writing here about movies that I’ve just seen on video or DVD, well after they’ve left the theaters and long after any initial excitement they may have stirred up has been dissipated. Unfortunately, with the way my life has worked over the past two years, I see far more films on my DVD player than at the cineplex. So more often than not, I’ll just choose not to write about them at all, but in the case of “School or Rock,” how can I resist?

Excepting the fact that it is itself a kind of further mitigation of anything that was once powerful or mortifying about rock ’n’ roll, “School of Rock” is probably the most successful cinematic affirmation of the music’s potential I’ve seen in forever. It has a magical way of making implausible, untenable farces like Pink Floyd, Led Zeppelin and AC/DC seem somehow invigorating.

Most of this is owing to Jack Black’s alarming lack of self-awareness and the manner in which he draws a brilliant cast of children into his cracked mirror of musicianship. The plot, which is thin and formulaic, can be considered a kind of vessel for the gift of watching Black interact with his youthful proteges; each of the scenes in which they jam together as a band is startlingly alive and joyful. In fact, I haven’t seen anything so infused with sheer energy and vibrance while set to a rock ’n’ roll beat since the Beatles ran laughingly down the black and white streets of London in 1964.