There have been at least 150 school shootings in the United States since 2013, an average of nearly one per week, according to the group, Everytown for Gun Safety.
The advocacy group created the map below showing the locations of those shootings.
To create the map, “school shooting” was defined as, “anytime a firearm is discharged inside a school building or on a school campus or grounds, as documented by the press and confirmed through further inquiries with law enforcement”.
Instances in which guns were taken to school but were not fired, or were fired off school grounds after having been on school grounds, are not included on the map.
In a 2014 report, Everytown for Gun Safety found that in 70 percent of the incidents, the shooters were minors and that nearly two-thirds of these perpetrators used guns they’d gotten from home. One-third of the shootings happened after a verbal argument or other confrontation.
Critics, such as John Lott, president of the Crime Prevention Research Center, take issue with Everytown’s numbers.
“A number of fact checks have found significant mistakes in Everytown’s report,” Lott said in an email. “Among their mistakes, they include: shootings that are off of school property and do not involve people who have anything to do with the school, legitimate self defense gun uses, and gang shootings and lone suicides that were well outside of school hours that do not involve anyone connected to the school.”
Deadly school shootings can have a profound impact on schools and student performance, according to a recent analysis.
Louis-Philippe Beland of Louisiana State University and Dongwoo Kim of the University of Missouri found that enrollment in 9th grade — the first year of high school — drops following a deadly shooting, but the numbers of students in the other grades do not.
Beland and Kim also found that standardized test scores in math and English drop for up to 3 years following a deadly shooting. Previous research suggests exposure to trauma can damage the hippocampus, a part of the brain that’s thought to be the center of memory and emotion.
The negative effects can last long after the students’ school years. Research shows adolescent victims of violence are more likely to suffer from depression as adults.