Spend time on any school playground during recess, and you will probably see what Jim Snyder’s research has proven:

It’s a jungle out there.

Amid the laughter and play, there is teasing, name-calling, poking, pushing and shoving. And it happens more frequently than you might think.

Snyder, a psychology professor at Wichita State University reports that children were targets of verbal or physical harassment about once every five minutes, based on observations of 266 kindergartners at a Wichita, Kan., school playground.

His research, conducted over two years and published in the journal Child Development, raises new concerns about bully behavior and its effect on even very young students.

“What was most surprising was just how much of it there was,” Snyder said.

The study found that harassment decreases as kids move on from kindergarten and “become more effective at dealing with it,” Snyder said.

But some children – about 10 percent of those followed in the study – become chronic victims, he said.

Parents of children who were frequent targets of playground harassment reported their kids showed more antisocial or aggressive behavior at home, or were more sad and withdrawn.

None of the findings surprises SuEllen Fried, author of “Bullies, Targets & Witnesses: Helping Children Break the Pain Chain.”

Fried says children should be taught about bullying even before school. “We need to start with day care centers and preschools, and we need to emphasize that bullying is not just physical,” she said.

“What’s far more prevalent and much more insidious is the verbal and emotional bullying – the teasing and name-calling,” she said.

Snyder’s team followed a group of students at a Wichita elementary school beginning in the fall of 1998. He has not named the school because of confidentiality concerns.

Trained observers watched the students several times at recess during their kindergarten and first-grade years, logging behaviors. Typical incidents ranged from the infamous “nanny nanny boo-boo” song to pushing and shoving while in line for the slide.

Much of the previous research on aggressive behavior relied on after-the-fact reporting by students, teachers or parents, Snyder said.

Researchers also asked teachers and parents to fill out questionnaires about students’ behavior, and tracked their overall academic performance.

They found that boys and girls behave differently on the playground and display different forms of aggressiveness.

Boys tend to run in large groups, “like a herd of antelope,” Snyder said. They value competition – who can run the fastest, swing the highest, etc. – and are more likely to tease “weaker” children.

Girls tend to relate one-on-one or in small groups and value cooperation. But that doesn’t mean girls aren’t aggressive.

“It’s more covert,” Snyder said. “It’s, “Did you see what so-and-so is wearing?’ or “We’re not going to play with you anymore.”‘

A growing challenge for teachers and playground monitors is teaching children that television behavior isn’t always appropriate, says Debbie McKenna, the Wichita district’s supervisor for safe and drug-free schools.

“We now have an entire school system of kids who have been raised on sitcoms,” she said. “Somebody puts somebody down, and the laugh track comes on. Then they slam back with another insult, and it continues. Kids learn that to be funny, you have to do it at somebody else’s expense.”

“We have to stop looking at teasing and name-calling as a rite of passage, or saying, “Kids will be kids,”‘ Fried said. “The awareness of bullying has gone up, but we can’t say we’re doing enough.”