In the 1967 classic To Sir, With Love, Sidney Poitier plays an innovative teacher who helps some tough East London kids succeed both in school and at home by taking a personal interest in their lives.

Fast-forward some 50 years and this type of positive approach remains the exception, not the rule. Middle and high schools are doling out suspensions at ever-higher rates; according to two recent reports, 2 million students were suspended during the 2009 school year, and boys of color and children with disabilities were suspended at much higher rates.

So it’s encouraging to learn about Lincoln High School in Walla Walla, Washington, which is bucking the trend with policies that keep kids in school and enjoying great success doing so. How great? Suspensions have dropped a whopping 85 percent. Given that Lincoln is an alternative school that takes on at-risk students whose behaviors have gotten them kicked out of other settings, its success rate is that much more remarkable.

So how does it work? Let’s say a student behaves negatively—maybe he hurls curses at a teacher. The go-to consequence in this time of increasing “zero-tolerance” is suspension; according to a 2011 report by the National Education Policy Center, 95 percent of kids are kicked out of school not for weapons or drugs but for categories including “disruptive behavior” and “other,” which includes being “defiant”—a vague, highly subjective term—cell phone use, dress code violations, displays of affection.

But this is not the case at Lincoln High; instead, teachers and administrators act quickly to stem escalation and try to find out what’s going on in the student’s life that might be causing him to act out. So principal Jim Sporleder might ask a student, “Wow. Are you OK? This doesn’t sound like you. What’s going on?” He gets even more specific: “You really looked stressed. On a scale of 1-10, where are you with your anger?”

Sporleder did his about-face after he learned the theories of John Medina, the best-selling author of Brain Rules. Medina writes, “Severe and chronic trauma (such as living with an alcoholic parent, or watching in terror as your mom gets beat up) causes toxic stress in kids. Toxic stress damages kid’s brains. When trauma launches kids into flight, fight or fright mode, they cannot learn. It is physiologically impossible.”

“It sounds simple,” Sporleder says about the new approach. “Just by asking kids what’s going on with them, they just started talking. It made a believer out of me right away.”

This is not about giving kids a pass. There are still consequences, just not punishment, which many consider less effective as a way to shape behavior. Instead, Lincoln uses ISS—in-school suspension, “a quiet, comforting room where the student can talk about anything with the attending teacher, catch up on his homework, or just sit and think about how maybe he could do things differently next time.” Sporleder and his staff also give kids the tools to recognize their reaction to stress and how to self-regulate their response to it.

The approach is in stark contrast with traditional suspensions, which don’t work well for kids who are already at-risk. “Studies show that one suspension triples the likelihood of a juvenile justice contact within that year,” California Chief Justice Tani Cantil-Sakauye told the California Legislature last spring. “And that one suspension doubles the likelihood of repeating the grade.” Meanwhile, according to the NEPC report, “research shows being suspended even once in ninth grade is associated with a 32 percent risk for dropping out, double that for those receiving no suspensions.”

Given the cost to students, parents, and society at large when kids aren’t encouraged to stay in school, Lincoln High offers an important lesson: When students are treated as individuals, when teachers and administrators take time to find out what’s behind their behavior, what’s happening in their lives that’s affecting them in school, the results can be stunning.