Richard Linklater’s “Boyhood” will certainly be much talked about for its singular shooting schedule. The writer-director made it in a very private way over more than a decade, filming for a few days each year to portray a boy named Mason growing up amid social change and familial turmoil, with the same actor portraying the part from age six to eighteen. The result will be compared by many to Michael Apted’s extraordinary “Up” series, which in installments made every seven years follows a group of English subjects from age seven to (as of now) fifty-six. But “Boyhood” isn’t a documentary; it’s a scripted film that Linklater fashioned bit by bit over the years as his young star, Ellar Coltrane, grew up himself, using the actor’s own personal experiences and interests to shape and deepen the script while adding his own dramatic impulses. It’s art reflecting life in an unusual way rather than a selective record of life itself.

“Boyhood” does, however, resemble Apted’s documentaries in one very important respect: it’s far more than the cinematic stunt the creative process might suggest. Even more brilliantly than in his “Before” trilogy, Linklater here manages to capture the passage of time and the growth that comes with it more perfectly than any other film in memory. Though at 165 minutes it’s epic in terms of running-time, it’s intimate in its concentration on Mason, whom we meet as a fresh-faced schoolboy and follow through his high school graduation and arrival at college. There are some high-pitched moments along the way, but for the most part the episodes have a gently ruminative, thoroughly naturalistic quality, marked by long sequences of conversation that are revelatory but low-key. And like life itself, it leaves much unexplained. What happened to this character, or that one—Mason’s best friend in the initial sequence, or his step-siblings in another—though some characters do reappear later on? Was there any follow-up to this scene (like Mason being bullied at school)? The fractured, untidy nature of the narrative is itself a moving commentary on how lives are really lived.

And although the film’s focus remains on Mason, we watch as others grow and change around him. There’s his older sister Samantha (played by Linklater’s daughter Lorelei), who first appears as a tyke tormenting her brother but grows into a college girl with a serious boyfriend (though she retains her attitude throughout). Even more importantly, there are his divorced parents Mason Sr. (Ethan Hawke) and Olivia (Patricia Arquette). He’s a would-be musician and “free spirit” who’s gone off to Alaska and comes back to Texas erratically to reconnect with the kids before moving back for good, remarrying and having a baby with his new wife. Olivia’s a harried single mom who goes back to school to earn a graduate degree and start a teaching career; but she also goes through two more marriages along the way, neither of which winds up happily-ever-after. It’s equally fascinating to watch these two as they grow and age along with their son, moving from a generalized fecklessness to a mature, seasoned sense of responsibility. And the unforced naturalism of all three actors complements Coltrane’s central performance, the anchor of the narrative, perfectly. The supporting characters are similarly well drawn down the line.

Linklater pushes nothing unduly, but throughout adds amusing touches dealing with technological progress that suggest the passage of time almost as tellingly as the physical changes in the characters. And without straining, he adds humorous touches to the dialogue and situations that the actors embrace. The laid-back attitude extends to the look of the film, shot by Lee Daniel and Shane Kelly without ostentation and edited by Sandra Adair to allow the scenes to breathe naturally. Details of place and dress are precise without being precious, and as usual with Linklater’s work, the music is carefully chosen.

The result is a film that’s profoundly moving in its deceptive simplicity of style and substance, one that captures the intermingled hopefulness, regret, joy and sadness of real life in a form that seems devoid of artifice but is actually very artistically sophisticated. Back in 1961, Pauline Kael remarked of Vittorio De Sica’s 1947 masterpiece, “If people cannot feel ‘Shoeshine,’ what can they feel?” It’s a sentiment one might repeat about Linklater’s remarkable film, an instant classic twelve years in the making, striking in its tender tone and stunning in terms of its cumulative emotional impact. “Boyhood” is one of the best films not only of the year but of the new century.