When previews of “American Teen” were screened on large overhead monitors in a giant sports bar during a party at this year’s South by Southwest Film Festival in Austin, Texas, the smartly edited montage of life at a Midwestern high school looked like a teaser for a new cable network series. One of the documentary’s selling points is its professional slickness, achieved on a remarkably slight $5 million budget, which adroitly packages a year’s worth of fly-on-the-laptop peeking into adolescent drama as if such raw, emotional, self-lacerating stuff were a sporty new skirt on sale at American Apparel.

And yet, it’s hard to imagine how the project might succeed any other way. Producer-director Nanette Burstein (“The Kid Stays in the Picture”) spent an entire school year with the senior class of 2005-06 at Warsaw Community High School, a 1,000-student mega-school that serves as an all-for-one class and racial melting pot in Warsaw, Ind. What she came back with seems to say as much about the hyper-mediated culture in which children now come of age as it does about the eternal verities of first love, hormonal overdrive, peer pressure, the nascent sadomasochism of campus pecking orders, sexual identity, and dysfunctional families.

Since the days of Robert Flaherty and the Inuits, documentarians have struggled with what physicists call “the Copenhagen interpretation”: how the act of observing alters the behavior of what is observed. Filmmakers such as D.A. Pennebaker tackled the issue in part by simply being around all the time — a smudge on the wallpaper — and using early handheld camera setups that minimized the need for distracting crews. But now, anyone with a Handycam and a cheap computer is their own Mr. Pennebaker, and a generation weaned on MySpace, YouTube, reality television, and amateur porn shot and distributed via cell phone is so completely self-aware and so instantly ready for its close-up that it’s hard to imagine it lapsing into a pure, naïve moment for a live-in Boswell.

Ms. Burstein probably sensed this going in, and she didn’t fight it. Her cameras track four primary characters whose personalities fall into familiar archetypes. The promotional campaign for “American Teen” plays this up, with a poster modeled on the iconography of the John Hughes hit “The Breakfast Club.” There’s a jock, Colin, who anxiously strives to win a basketball scholarship because his working-class family can’t afford college tuition (although there’s always wartime military service). There’s an iconoclastic, artsy girl, Hannah, who yearns to break away from her small-town life to become a filmmaker in the big city, but may be swallowed up in the undertow of depression. There’s her polar opposite, Megan, the über-blond mistress of all she surveys, whose casual cruelties eventually come back to bite her.

And, perhaps most touchingly, there’s Jake, the pimply band geek, whose keenly articulated struggle to find and keep a girlfriend gives the film its most genuinely affecting moments — perhaps because Jake’s profound self-loathing allows for no vanity or posturing, but a lot of honest, painful humor. He’s the real version of one of Judd Apatow’s fantasy video-game-addicted virgins, something with which Ms. Burstein has imaginative fun, embellishing Jake’s agonies with animated sequences that translate his travails into a Dungeons-and-Dragons-style romantic epic.

Other teenagers pass through each of the principals lives, either as sidekicks, rivals, or romantic attachments, but parents are rarely seen. And while the film doesn’t suggest that these teenagers are particularly wild, there’s enough misbehavior — implied and otherwise — to emphasize their adolescent rebelliousness. In one particularly hurtful sequence, the evil Megan comes into possession of a nude photo of a female classmate that is quickly sent via e-mail through their social network. To make matters worse, she enlists her friends to prank call the unfortunate girl — who only wanted to impress a guy she liked — and denounce her as a slut.

Meanwhile, the bright and promising Hannah gets dumped after she gives up her virginity to her longtime boyfriend and goes into a tailspin. She nearly drops out of school, but finally musters up the courage to return. Just as she regains her momentum, and focuses on a move to San Francisco and art school, she begins an unexpected romance with the school’s hunky big man on campus, who has become bored with the Barbies and sees Hannah as a challenging enigma. If this were a John Hughes movie, the title credits could roll. Of course, it doesn’t work out that way.

What’s likable about “American Teen,” besides the generally sympathetic woes of its teenagers, is how Ms. Burstein insists on peeling away the layers with which her teenagers construct their own identities, and which they project onto their peers. Even spoiledMegan has a tragedy in her family closet that makes her more sympathetic, and if the film works overtime at making Hannah its heroine, it also reminds the viewer how painfully self-absorbed a 17-year-old can be.

It’s probably impossible to expect anyone to come up with a documentary as powerful as Joel DeMott and Jeff Kreines’s “Seventeen,” which in 1983 traced the lives of another group of Midwestern teens with risky, gut-punching social realism. The film, broadcast on PBS, is out of circulation but you can YouTube it here (www.youtube.com watch?v=Edgk61qq7cw). Obscure as it is, “Seventeen” has, in retrospect, the advantage of being shot on the cusp of the MTV era (a big moment comes when the teenagers play Bob Seger’s “Against the Wind” as a eulogy for a pal who has been killed in a car accident). “American Teen,” for all its seeming 24/7 access, never feels terribly vérité. Its subjects sport their remote transmitters on their belts like the latest hip accessory. Yet that may be the most telling element of all.