On April 20, 1999 a school shooting in suburban Denver shook the country.

Now, 20 years after the shooting, some kids who survived it are having kids of their own. A generation of America’s children have gone through lockdown drills. There have been more mass shootings, which have created thousands of survivors knit together in a network.

Columbine created a need to feel supported and created a need to understand how to stop the next "Columbine." Hosted by Colorado Public Radio reporters Andrea Dukakis and Nathaniel Minor, this podcast series tells stories of how one shooting changed America and what we’ve learned since.