Many Columbine students said they knew the youth arrested.
Last month, two more Columbine students were shot to death in a sandwich shop for reasons that are still unclear to investigators.
Still shocked by the attack, Columbine students and their families received several morale boosters in recent days.
In the aftermath of the shooting, many Columbine students found a refuge in church.
Many questions remain for some parents of Columbine students.
His younger sister, Lisa, also a Columbine student, escaped unhurt.
Some 1,400 Columbine students had gathered in the gym for the pep rally.
And they express hate as well for young athletes and other Columbine students more popular than they.
Two months later, two other Columbine students were shot to death in a sandwich shop just blocks from the school.
On April 20, 1999, two Columbine students killed 12 students and a teacher before taking their own lives.