The TV show Glee might be a bit overdramatic in the way it depicts more-popular high-school students’ tossing slushies at glee-club members, but it has the general right idea.

Bullying has a lot to do with popularity, according a new study by the University of California at Davis.

The study suggests that bullying largely is motivated by a desire to climb the social ladder, as opposed to trying to compensate for trouble at home or other personal problems, as many assume.

“This is not to say that both things aren’t happening at once,” said Robert E. Faris, one of the study’s authors and an assistant sociology professor at UC. “But by and large, our study found that it was about social status, even more than demographics or socioeconomics.”

Other studies have estimated that bullying hurts as many as 5.7 million children in the U.S. each year.

A small percentage of popular kids at the very top of the social hierarchy tend to be less aggressive, probably because they’ve reached the top and have no need to bully, Faris’ study says. But other than that, the more popular students become, the more they act out. Boys were more prone to physical bullying than girls, who leaned more toward passive-aggressive acts and needling comments.

Those at the bottom of the food chain were less likely to bully, partly because they lack the clout with their fellow students to get away with it.

The study looked at 4,000 high-school students in North Carolina, mapping their relationships and bullying habits. Overall, most students weren’t aggressive.

Jim Bisenius, a bullying expert based in Pickerington, said the study might be an oversimplification, but it matches what he has seen in interviews with bullies and their victims. Bisenius runs Bully-Proofing Youth, which provides training to prevent bullying.

There are three types of bullies in his experience: spoiled children without a sense of limitations; neglected children who lash out for attention; and high-pressure achievers set on climbing the social ladder.

Social climbers are different from truly popular teenagers because they rely on control, intimidation and politics instead of genuine likability, Bisenius said. Girls will sometimes use fear of exclusion from the group to keep “followers” in line, and they’ll systematically break up friendships that threaten their authority.

“These kids think strategically like little chess players,” he said. “Their bullying is still based on insecurity, but it’s much more planned and plotted than I would ever have thought initially.”

Psychologists used to think that bullies tended to be children with poor social skills, but increasingly they’re realizing that the stereotypical image of a bulky kid stealing lunch money is outdated, said Kisha Radliff, an assistant professor of school psychology at Ohio State University.

Radliff said a lot of bullies are students who do well in school and seem sweet – when teacher isn’t looking.

The UC study is important, she said, because it gets the word out that there’s more than one factor in bullying.

If bullying is a matter of power, Faris said, he hopes adults will find ways to discourage students from letting aggression dictate a classmate’s status.