Deepertruth: "Why are kids killing kids at school."

When an Ohio high school student killed three classmates in a shooting rampage several weeks ago, it once again brought a national spotlight to a problem widely believed to be epidemic in schools.

The reality, experts say, is exactly the opposite: Violent crime in schools has decreased significantly since the early 1990s.

Not only are rates of school violence going steadily down, but it's clear that schools are the safest place for a student to be.

Stephen Brock of California State University, Sacramento

Dewey Cornell, a clinical psychologist and education professor at the University of Virginia, says incidents like the one in Chardon, Ohio, and the infamous mass shootings at Columbine High School in Colorado and at Virginia Tech have reinforced a perception that schools are dangerous places.

"But that's just not true," says Cornell, who has been examining school violence for decades. "I know on the heels of any school shooting, there's the perception that violence is on the rise. It's not. In fact, there's been a very steady downward trend for the past 15 years."