"An overwhelming number of kids who call here feel outcast in some way -- not that they are outcasts -- but that's the way they are feeling," says Ross Greenman, a teen line listener.
It's an age-old adolescent complaint but many teens say the struggle for belonging and a sense of self is harder these days. Some can relate to the sense of alienation that drove Eric Harris and Dylan Klebold to kill.
"I don't condone what they did, but I can see why they did what they did. If they were that alienated I guess they figured, 'If I'm going to die, I'm going to take a bunch of kids with me,'" one teen said.
Psychologists believe that children are subjected to increasing academic and social pressures today. For some kids the stress can transform typical feelings of alienation into something much darker: depression.
"In many ways, this is a public health crisis," says Dr. Peter Jensen of the National Institutes of Mental Health.
Jensen says that as many as five to ten percent of children aged 9 to 18 suffer from depression. It can lead to suicide without treatment, and because childhood depression is often overlooked, only one in three kids gets help.
"In the incidence of suicide, most of those children were indeed depressed. If we could have gotten to them before, we could have helped them," Jensen says.
Eric Harris was reportedly taking anti-depressants, but whatever treatment he might have been getting did not come early enough to stop him from killing others and evidently taking his own life.
"This particular death spiral kept going and going and going and no one stopped it," psychologist Richard Gelles says.
Gelles believes the shooting spree was the result of a free fall of depression: beginning with alienation and ending with suicide.
"They were non-entities," Gelles says. "That's the worst thing that can happen to a 16, 17 or 18-year-old, or for that matter any human being, to feel that they don't exist. And what you saw was a trail that was leading to suicide."
Not all childhood depression explodes into violence, but it's not a stretch to imagine how it happens: just ask any teenager who's felt left out.
"Nowadays, kids can be more cruel. And so a lot..a lot of students in turn build up a lot of anger within themselves," one teen-age girl says.
Psychologists say the key for parents is to pay attention -- to recognize when garden-variety teenage rebellion develops into total detachment. Turning the once unthinkable into something we're now struggling to understand.
Reported By Elizabeth Kaledin