Come to think of it, I wasn’t sure if the American approach had ever worked very well. My students in the States had always seemed to drag their feet after about 45 minutes in the classroom. But they’d never thought of revolting like this shrimpy Finnish fifth grader, who was digging in his heels on the third day of school. At that moment, I decided to embrace the Finnish model of taking breaks.

Once I incorporated these short recesses into our timetable, I no longer saw feet-dragging, zombie-like kids in my classroom. Throughout the school year, my Finnish students would—without fail—enter the classroom with a bounce in their steps after a 15-minute break. And most importantly, they were more focused during lessons.

At first, I was convinced that I had made a groundbreaking discovery: frequent breaks kept students fresh throughout the day. But then I remembered that Finns have known this for years; they’ve been providing breaks to their students since the 1960s.

In my quest to understand the value of the Finnish practice, I stumbled upon the work of Anthony Pellegrini—author of Recess: Its Role in Education and Development and emeritus professor of educational psychology at the University of Minnesota—who has praised this approach for more than a decade. In East Asia—where most primary schools give their students a 10-minute break after 40 minutes or so of classroom instruction—Pellegrini observed the same phenomenon that I had witnessed at my Finnish school. After these shorter recesses, students appeared to be more attentive in the classroom.

Not satisfied with anecdotal evidence alone, Pellegrini and his colleagues ran a series of experiments at a public elementary school to explore the relationship between recess timing and attentiveness in the classroom. In every one of the experiments, students were more attentive after a break than before a break. They also found that the children were less attentive when the timing of the break was delayed—or in other words, when the lesson dragged on.

In Finland, primary school teachers seem to know this intuitively. They send kids outside—rain or shine—for their frequent recesses. And the children get to decide how they spend their break times. Usually, teachers in Finland take turns—two at a time—supervising the playground during these 15-minute stints.

Although I favor the Finnish model, I realize that unleashing fifth graders on the playground every hour would be a huge shift for most schools. According to Pellegrini, breaks don’t have to be held outdoors to be beneficial. In one of his experiments at the public elementary school, students had their recess times inside the school and the results matched those of other experiments where students took their breaks outside: After their breaks, the children were more attentive in class.