A “To Sir with Love” for a new generation, Mexican drama “Radical” from writer-director Christopher Zalla (“Blood of My Blood”) features an award-worthy turn by superb lead actor Eugenio Derbez as an idealistic teacher of disadvantaged children and break-out turns by several members of its youthful cast. The film, based on a Wired article, tells the tale of Sergio Juarez Correa (Derbez), a sixth-grade teacher at Jose Urbina Lopez Primary School in Matamoros, Mexico in 2011, where gangs employ and recruit school-age boys. Heavily-armed soldiers maintain checkpoints, and schools are in decline.

On his first day at a new post, Sergio runs afoul of the principal whose first name is Chucho (a fine Daniel Haddad), as well as a jaded fellow teacher. Some of Sergio’s students are experiencing “pubertad.” Others look more like children. In spite of her diminutive size, Lupe (a fiery Mia Fernanda Solis) is cook and caregiver at her home, where her mother has just had another baby. Sergio learns that the encyclopedias in the school library are circa 1974 and that the computer lab was robbed. In fact, the only person with a computer is Chucho. Outside, police tape is unwound around dead, bullet-riddled bodies in the street. Inside, Sergio is trying to unlock young minds and avoid getting fired.

A student named Nico (a terrific Danilo Guardiola) carries a red backpack with him. He’s not sure what’s in it. But he does it every day for a violent gang leader. Nico has a crush on Pamola (a powerful turn by Jennifer Trejo), who lives in a beach shack with her sickly junk-peddler father, who collects scrap metal with his cart and donkey. Just outside Paloma’s door is a mountainous landfill, where Paloma fishes for things she can use or give to her father to sell. She also finds books and magazines that she keeps hidden in her room, portals to other worlds. She wants to be an astronaut. Based on her power of comprehension, Sergio thinks that Paloma might be a genius.

The gang leader ridicules school work and tells Nico that he must learn from “la vida.” If “Radical” were a musical, this would be a cue for a song and dance number. Sergio inspires his students by telling them that, while they may not have what others have, they all have one thing in common: potential. Using bits found in the landfill, Paloma builds a telescope. Sergio shows Nico another path.

Films about inspiring teachers include everything from “Goodbye, Mr. Chips,” “Mr. Holland’s Opus,” “Stand and Deliver,” the aforementioned “To Sir with Love,” “Lean on Me,” “Dead Poets Society” and beyond. This trope is popular and powerful because so many of us have been inspired and transformed by a great teacher. Sergio is far from a know-it-all. He keeps admitting to ignorance in front of his students. But he knows how to teach and gently guide. The children adore him because he passionately believes in them. Writer-director Zalla, adapting the article by award-winning author Joshua Davis, keeps Trejo, Solis and Guardiola front and center and teases sweet and mature performances out of them. If you aren’t getting teary-eyed at the end, you may need a cardiac tune-up. Derbez (“Batteries Not Included”), one of the most well-known Hispanic actors in the world and a secret ingredient in “CODA,” lets us see the demons that torment Sergio and dwell right inside his head, but also drive him to greatness as a human being. Surely, this performance should generate Oscar buzz.

(“Radical” contains violence, mature themes and strong language)

“Radical”

Rated PG-13. In Spanish with subtitles. At the AMC Boston Common and AMC Methuen. Grade: A –