May 20, 1999: Several people are wounded in a shooting at Heritage High School in Conyers, Ga., near Atlanta. The person believed to be the shooter (identified by some students as a classmate) is taken into custody.
April 20, 1999: Two student gunmen at Columbine High School in Littleton, Colo., kill 13 people and place bombs throughout their school before taking their own lives.
April 16, 1999: A high school sophomore fires two shotgun blasts in a school hallway in Notus, Idaho. No one is injured.
June 15, 1998: A 14-year-old student allegedly opens fire in a hallway of Armstrong High School in Richmond, Va.
May 21, 1998: Two teen-agers are fatally shot and more than 20 people are hurt when 15-year-old boy allegedly opens fire at high school cafeteria in Springfield, Ore. His parents are found slain at their home. He is awaiting trial.
May 19, 1998: Three days before his graduation, an 18-year-old honor student allegedly opens fire in parking lot at Lincoln County High School in Fayetteville, Tenn., killing a classmate who was dating his ex-girlfriend. He is awaiting trial.
April 24, 1998: A science teacher is shot to death in front of students at eighth-grade graduation dance in Edinboro, Pa. A 14-year-old student awaits trial.
March 24, 1998: Four girls and a teacher are shot to death and 10 people wounded during false fire alarm at middle school in Jonesboro, Ark., when two boys, 11 and 13, open fire from the woods. Both are convicted in juvenile court of murder and can be held up to age 21.
Dec. 1, 1997: Three students are killed and five others wounded in a hallway at Heath High School in West Paducah, Ky. A 14-year-old student, Michael Carneal, is arrested. One of the wounded girls is left paralyzed.
Oct. 1, 1997: A 16-year-old boy in Pearl, Miss., is accused of killing his mother, then going to his high school and shooting nine students, two fatally. The boy, Luke Woodham, is sentenced to life in prison. Two others await trial on accessory charges.