Columbine High School Massacre

The campaign was launched by the parents of a victim of the Aurora, Colorado, theater massacre.
The shooting left one student with an injury that wasn't life-threatening.
Photos from around the country show students marching on the anniversary of the Columbine High School shooting.
Former Columbine High School Principal Frank DeAngelis is dealing with loss and trauma through counseling and faith.
Friday's walkout was somewhat smaller than a similar walkout in March.
In the past few months, hundreds of thousands of young Americans have taken to the streets to demand tighter gun laws.
Heather Martin and Zachary Cartaya's nonprofit, The Rebels Project, works to connect survivors of mass shootings to one another through a private nationwide network.
“I’m so proud of them, and I don’t even know them.”