Five of these alleged young assassins have planned to set off bombs in school and then shoot their classmates in the confusion. Some even borrowed the trench coat look made infamous at Columbine. The student charged in the most recent incident, in New York, had 14 pipe bombs, three smaller bombs, a propane tank, a sawed-off shotgun, a .22-caliber pistol and a book bag full of ammunition.
What's disturbing is that most of the wannabe killers are described as outcasts who came to see murder as a form of social revenge, CBS News Correspondent Wyatt Andrews reports.
"This one boy was dead serious. He had this anger in him and he meant to hurt someone," said Sheriff Eddie Shoffner of Claiborne County, Tenn., where one of the most recent would-be episodes was averted.
But the legacy of Columbine is not all bad. Every one of these copycat plots has been reported by students, so clearly, the code of silence no longer covers incidents that could kill classmates.
"They was going to set more than one pipe bomb off, they wanted to kill everybody. They didn't want nobody to come out," said one teenager who helped stop a rampage in Claiborne County, Tenn., this week.
He said the Columbine incident two years ago "was the first thing that come to my mind."
But what has changed since Columbine is not just that students will report other students. It's also that the schools and the police are taking the reports they get seriously.
Shoffner admitted just two years ago he might have downplayed reports of pipe bombs, but this time, "in a matter of 30 minutes, I had 16 officers at Powell Valley High School," he said of the school that was targeted.
It's the same at schools, where there's no more tolerance of threats. There's no more "boys being boys," or acceptance of students violently acting out, or threatening to, said Larry Anderson, principal at Powell Valley High School.
"We can't afford that. For the safety of our students, we can't afford that," Anderson said.
Maybe Columbine taught the outcasts how to attack their schools, but the rest of the country's learned something too: to watch for the anger that can give rise to outbursts. Now, they know no place is immune.