Under a zero-tolerance policy to prevent school violence, a 6-year-old is kicked out for carrying camping gear

Gitta Sereny ponders the Colorado killings.

The kids who survived the worst school massacre in U.S. history have graduated, and some of them have even forgiven. But many of their parents have not.

What turns an angry, alienated teen into a school shooter -- and what can we do it about it?

The Columbine killers left videos for police to find after their rampage.

Littleton killers didn't quite fit in, even with the "Trench Coat Mafia."

Outcasts who grew up without resorting to violence talk about what kept them from a Littleton-style massacre

What little we know of the Columbine killers' motives points to the dangers lurking in dark, Nazi-worshiping corners of alienated youth culture.

Mark Manes gets six years in prison for supplying one of the weapons used in the Colorado high school massacre.

We point you to the highlights in a true-crime chronology of the high school killing spree

White criminals are often treated better by the press than black victims like Michael Brown and Trayvon Martin

A renegade researcher believes the teenage killers of Columbine could have been driven to crime by environmental poisoning.

In the wake of new chat room threats and the release of the killers' videotapes, wary school officials cancel the last two days of class.