High school students Kerron Hayes, left, and Cameron Perry work on a chicken coop project in the documentary “If You Build It.” (Long Shot Factory)

Can a chicken coop make you cry?

The answer is a definite yes in “If You Build It,” a bracing, quietly exhilarating documentary about a group of high school students who discover their inner architects over the course of an academic year. Under the tutelage of an idealistic couple of committed design-builders, these teenagers — whose tiny hometown of Windsor, N.C., is quickly succumbing to brain drain and rural blight — start small and end big, stopping along the way to come up with whimsical, colorful and utterly gobsmacking ways to house a common farm fowl.

The coops are just some of the more delightful elements of “If You Build It,” which chronicles the sojourn of Matt Miller and Emily Pilloton, a pair of young designer-activists who arrive in Bertie County in order to redefine vocational education and turn it into a vibrant, hands-on workshop where kids learn the rudiments of critical thinking, technical skills and community engagement. Buckminster Fuller is invoked in “If You Build It,” but the individual who hovers over it like a benevolent spirit is Samuel Mockbee, whose radical humanism and grass-roots construction methods seem to inform every joist and beam.

Filmmaker Patrick Creadon (“Wordplay,” “I.O.U.S.A.”) gracefully threads viewers through a story that commences with bright-eyed optimism, then inevitably runs afoul of entrenched local bureaucracies. (One of the film’s subtle themes has to do with the political work that’s just as crucial to the design process as the marriage of form and function.)

But even when the students learn heartbreaking lessons about administrative short-sightedness and bad faith, it's impossible to leave “If You Build It” feeling depressed, largely because of the young people themselves. The film’s appealing cast of real-life players includes a sensitive farmer’s son named Stevie, a gifted football player named Erick and a loner named Kerron, all of whom evince genuine imaginative and observational talents.

Like last year’s “Nebraska” and “Medora,” Creadon’s “If You Build It” lifts an otherwise forgotten community, existing in a ghostly netherworld between past and present; if these gentle, sweet-natured young people are any indication, Windsor, at least, has a future. And, seriously, you’re not going to believe those chicken coops. Tear-jerkers, each and every one of them.

★ ★ ★

Unrated. At Landmark’s E Street Cinema. Contains nothing objectionable. 85 minutes.