May 18, 1927 Bath, Mich.: Andrew Kehoe, a school board official, kills his wife, then blows up the town's school and himself, killing a total of 44 people, including 39 students and teachers.
Aug. 1, 1966 Austin, Tex.: Charles J. Whitman kills 17 and injures 31 from atop the University of Texas tower.
May 1, 1992 Olivehurst, Calif.: Eric Houston, 20, holds dozens hostage at his former high school, Lindhurst High. During the standoff, Houston fatally shoots three students and one of his former teachers.
Dec. 1, 1997 West Paducah, Ky.: Michael Carneal, 14, fatally shoots three classmates and wounds five at a high school prayer meeting.
March 24, 1998 Jonesboro, Ark.: A 13-year-old boy and his 11-year-old cousin open fire outside a middle school, killing four girls and a teacher and injuring 11 others.
May 21, 1998 Springfield, Ore.: Kip Kinkel, 15, fatally shoots two students and wounds dozens after being suspended a day earlier for bringing a gun to school.
April 20, 1999 Near Littleton, Colo.: After planning for a year, Eric Harris, 18, and Dylan Klebold, 17, kill 12 students and a teacher and wound dozens before killing themselves at Columbine High School.
March 21, 2005 Red Lake, Minn.: On an Indian reservation, Jeff Weise, 16, kills his grandfather and a companion, five fellow students, a teacher and a security guard before killing himself.
Oct. 2, 2006 Nickel Mines, Pa.: Charles C. Roberts IV, 32, shoots 11 girls execution-style at an Amish school, killing five of them and wounding seven.