The fatal shooting of a principal at Weston High School on Friday in Sauk County could have been a killing triggered by other school shootings in the past month, experts say.

Three other school shootings, two of them leading to student deaths, have occurred at schools in North America since Aug. 30. Also, an alleged plot to kill students was thwarted in Green Bay.

Experts say the incidents - in North Carolina, Montreal, Colorado and now Wisconsin - could forecast a violent school year to come.

"The way this year has started out, this could be one of the most violent school years we're going to see," said Jared Lewis of Jefferson, a former California police officer who has written a book on profiling school shooters.

"If other students already have the idea and they see the public concern over this," Lewis said, "it might be the motivating factor to say, 'Alright, today is the day.'"

Joanne Cantor, a retired UW-Madison professor of communications who studies the impact of media violence on youth, said there "might be a copycat aspect" to Friday's shooting.

Parents should curb children's exposure to coverage of the incident, especially on TV, Cantor said.

Children under age 8 or so probably don't need to know about the shooting, she said. For older ones who are likely to hear about it anyway, it's better for parents to discuss it with them before children learn about it from their friends or the media.

'More accessible'

Joe Newman, chairman of psychology at UW-Madison, said reports of shootings can make gun violence seem like more of an option among students who are already hostile or depressed.

"It becomes more accessible," he said. "The more that kids hear about other kids doing it, the more they try that idea on for size."

Schools need to better assess mental health problems among students and refer students with problems for treatment, said Dr. Marcia Slattery, a UW-Madison psychiatrist on an American Psychiatric Association committee dealing with mental health and schools.

Little screening is done at schools in Wisconsin and other states, in part because of cost, Slattery said.

"Right now, there's no standard, consistent measure," she said.

Friday's shooting will be especially difficult for the Sauk County community of Cazenovia to deal with because Weston School educates students from kindergarten to 12th grade, said Dr. Gwen McIntosh, a UW-Madison pediatrician who studies school violence.

'Mayberry syndrome'

"These students are going to be coming back year after year to the same facility where a traumatic event happened," she said.

Lewis, the former police officer, said school shootings often occur in small towns because students who feel different are less likely to find a peer group and authorities may not take behavioral problems among students seriously.

"They get that Mayberry syndrome, thinking it couldn't happen here," he said.

But McIntosh said most school homicides and suicides are at urban schools.

Whether in big cities or small, schools account for less than 2 percent of all youth homicides, McIntosh said.

"Schools are one of the safest places to be," she said. "They're far safer than driving on the road or being at the mall."