Bullying in high school is not just a problem of individual torment: It is linked to lower academic achievement across the school.

So concludes research that investigated student behavior in nearly 300 high schools in Virginia, including most of those in the Washington suburbs.

The research shows that high school campuses with more reported bullying had lower passing rates on Virginia’s standardized tests.

“Bullying had a schoolwide impact, and we were able to show it reduced the level of academic engagement and involvement in student activities among students as whole,” said co-author Dewey Cornell, a professor at the University of Virginia who studies school safety.

Schools with high levels of reported bullying had lower passing rates — by an average of 3 to 6 percent across tests — when compared with schools with less reported bullying. The gap was reflected on state exams in algebra, world history and earth science, which factor into how Virginia rates its schools.

The findings coincide with increasing public concern about bullying. On Thursday, one of the nation’s toughest anti-bullying laws took effect in New Jersey, where a Rutgers University freshman committed suicide after a sexual liaison he was involved in was streamed over the Internet. Other states have also passed or considered changes, and the White House hosted a conference this year on the problem.

The Virginia research supports findings on the effects of bullying on elementary school students, said Marlene Snyder of the Olweus Bullying Prevention Program, which is based at Clemson University and is used in more than 6,000 U.S. schools. “It builds on what we know about what kids need to be successful,” she said.

The findings in Virginia — part of an ongoing school safety survey — are based on questions answered in 2007 by 7,300 ninth-graders and 3,000 teachers, all randomly selected, to assess levels of bullying and teasing in school.

Bullying was defined as “the use of one’s strength or popularity to injure, threaten or embarrass another person on purpose.” It did not include incidents when “two students of about the same strength argue or fight.”

Researchers said they hoped to show educators and others that success in testing goes beyond academic instruction and preparation. “Our study suggests that a bullying climate may play an important role in test performance,” they wrote.

The study, co-written with graduate student Anna Lacey, was presented last month at the annual conference of the American Psychological Association. A number of journal articles are in progress.

Test performance is influenced by many factors, and researchers controlled for characteristics such as school size, student poverty, race and ethnicity. Cornell said that in many instances, the level of bullying in a school mattered as much as poverty.

He had ideas about why this is so: “The likely explanation is that students are less engaged in school, and perhaps more are distracted. Teachers are probably burdened with more discipline problems, and there is just less goodwill and motivation in a school where students experience a lot of bullying and teasing.”

In related research, Cornell and others found that schools with more reported bullying had higher dropout rates. They also categorized discipline approaches in Virginia high schools according to four styles of parenting: authoritarian, authoritative, permissive and indifferent.

The schools that used the “authoritative” model — firm and demanding in discipline, but warm and supportive toward students — had the least reported bullying and teacher victimization.

Statewide, 104 schools were rated as authoritative; nearly 100 were rated in what researchers consider the lowest category, indifferent. The analysis included 290 public high schools, about 92 percent of the state’s total.

Justin Patchin, an associate professor at the University of Wisconsin at Eau Claire and co-director of the Cyberbullying Research Center, said the findings on campus bullying dovetail with his work on online bullying. “Schools and classrooms that have a positive climate or culture have students that get into fewer problems online, outside of school,” he said.

Randi Mack, a Fairfax County mother of two, said she hoped that the message of the study would have an impact. “Unless you have a warm, nurturing environment, kids can’t learn,” she said. “It just reinforces an intuitive truth.”