Just who is the target audience for “Les Choristes” (The Chorus)? The straightforwardly told story, set in post-World War II France, concerns a quiet, warmhearted, middle-aged schoolteacher who transforms some rambunctious schoolboys through the power of song.

It could be meant for young children – yet there are just enough inappropriate references and one powerful disciplining scene to negate that theory. It was a hit with the adults in France, though (indeed, according to the French Institute, it lead to a surge in choir membership across the country). But if indeed it is intended for grown-ups, it is too naive, and far too serious, to be taken seriously.

At the beginning of the film, we meet an older, internationally revered maestro named Pierre Morhange, waving his arms as he conducts some celebrated orchestra. A surprise visit by an old schoolmate sends the film into its main narrative, which recounts a seminal year the two spent as youths at the very appropriately named Fond de L’Etang (Rock Bottom), a school for delinquent boys.

Christophe Barratier, in his debut, writes and directs, and in both endeavors, he favors a direct, uncomplicated manner that creates some memorable characters and sustains narrative interest. The film showcases the stereotypical assortment of misdeeds that a group of prepubescent boys has to offer: throwing paper, taunting, smoking, making fun of the teachers.

Its greatest asset is its verismo quality, which can be observed in the set and costume designs, as well as in the boy actors themselves, most of whom are nonprofessional. The standout among them is also the main character, the young Pierre Morhange (Jean-Baptiste Maunier). With a systematically sullen expression, Mr. Maunier invites both empathy and intrigue; in addition, he displays impressive boysoprano chops in his extensive solos with the choir.

As Clement Mathieu, Gerard Jugnot offers an understated and gracious portrait of an instructor who wins over his skeptical and recalcitrant audience. Distressingly, however, we never get a true sense of how his charges’ musical progression actually takes place: They change from a group of intonation challenged little thugs to the Vienna Choir Boys overnight.

The most comic relief comes from Rachin (Francois Berleand), the overbearing and downright wicked headmaster – although certain aspects of his character remain unconvincing. With his bow tie, chain watch, and harsh rules, Rachin appears very old school. So why, I wondered, would he be opposed to music in school, especially when it was espoused by Plato as – along with arithmetic, geometry, and astronomy – part of the Quadrivium? (Other, that is, than the requirements of the plot.)

Many of the other characters don’t convince at all, especially Mondain (Gregory Gatignol), one of the older children and certainly the most unruly, who – at least to this viewer – seems to displays serial-killer tendencies out of keeping with the generally innocent spirit of the film. Also forced is the episode in which Mathieu makes a play for Morhange’s mother, Violette (Marie Bunel). A cynical interpretation would be that this interest was included to ward off any suggestions of pedophilia – a subject one of the boys makes a quick and veiled reference to in the film.

“Les Choristes” is a light, benign, and superficial film that will offend few and undoubtedly please many. Still, the idea of the transformative power of music has been rehearsed a thousand times in film (“Sister Act” “Mr. Holland’s Opus”), and despite being French, this one doesn’t offer a fresh perspective.