In 2006, an idealistic New York public schoolteacher named Kevin Greer joined the faculty of an idealistic new high school, Brooklyn Community Arts and Media. Greer had previously taught English to 12th grade honors students at Dewitt Clinton, a huge high school in the Bronx. At B.C.A.M., which hoped to inspire students with an arts-driven curriculum, he would be teaching ninth graders. Most of the students had not chosen B.C.A.M., but had simply been assigned to the school. They weren’t nearly as self-motivated as Greer’s former students. Many if not most of them read below grade level.

Greer’s first approach to teaching these students was to refuse to concede to their obvious difficulties. He taught Plato and lectured about such things as “the rhetorical strategy of repetition of a phrase at the beginning of clauses. We call it anaphora.” He seemed distant from the students, and they reacted in kind, yawning or talking among themselves. Greer knew he was not getting through to them. He was frustrated.

Three years later, when members of this first B.C.A.M. class were seniors, Greer decided to teach a poetry class revolving around William Blake’s “Songs of Innocence and of Experience.” This time, however, his demeanor was completely different. He engaged the students by asking them what their own definition of poetry was — and they responded eagerly. He was more relaxed and more confident. “I had to learn how to really break things down,” he told me recently. “I had to learn to work on several levels at a time.” Because, after all, he had students of various abilities in his classes.

I know these details about Kevin Greer’s classroom performance because I recently saw a documentary about B.C.A.M. that has been passed from teachers’ group to teachers’ group, from reformers to union executives, like samizdat. The film, called “The New Public” and produced and directed by a filmmaker named Jyllian Gunther, tracks that first B.C.A.M. class in both the class’s first and last years at the school.

Once she finished the film, Gunther sent it around the various film festivals. None of them bit. “The New Public” was shown once on PBS, but aside from that, it has not been seen widely. Instead, teachers — as well as those who teach teachers — have slowly found out about it and have embraced it.

Partly this is because it is the rare film that sympathetically conveys how hard it is to be a teacher in an inner-city school. “The New Public” not only shows what goes on in the classroom — which can be rough if the teacher can’t manage the classroom — but she also goes into the homes of the students she has focused on. There, the odds that the students are trying to overcome are made abundantly clear.

But it is also because the movie is an unwitting primer on how to teach disadvantaged students. There are teachers in the movie who know how to connect with their students, and teachers who don’t. Teachers College at Columbia University liked the film so much that it is creating a companion curriculum, so the film can be used to help train teachers. Until Gunther’s movie came along, Teachers College used to show “The Wire” to give prospective teachers a feel for what it’s like to teach in a disadvantaged community.

“What is good teaching?” asked Anand Marri, a professor at Teachers College who has championed the film. “Is teaching different in the Bronx versus the suburbs? How much do you start with where the students are?” For the most part, these elemental questions are ones that schools of education don’t ask nearly enough.

The lack of teacher training in education schools has also been borne out recently by a new report by the National Council on Teacher Quality, entitled “Training Our Future Teachers.” The question the group asked was a simple one: Do education schools teach classroom management? The answer was: not very much.

The group examined 122 teacher-preparation programs and found that while most programs could say they had classroom management as part of their curriculum, classroom management strategies rarely received “the connected and concentrated focus they deserve.” What’s more, “instruction is generally divorced from practice (and vice versa) in most programs, with little evidence that what gets taught gets practiced.” Education schools, says Kate Walsh, who leads the group, “don’t see their job as training teachers. They see their job as creating professional identity.” As the country continues to struggle with education reform, it seems obvious that education schools need to change, so that prospective teachers walk into their first classroom knowing how to teach. Maybe “The New Public” can help bring about that change.