NPR.

You really only have to hear one word in the following news clip to know exactly what the reporter is talking about.

At least two gunmen opened fire today at Columbine High School

in Littleton, Colorado. There were many injuries in-Columbine, April 20th, 1999. 15 people were killed

that day, including the two gunmen. Another 20 were shot but survived. And another victim recently

died from complications related to her injuries.

Columbine wasn't the first school shooting, but for many Americans, it marks a turning point, the beginning of a dark era.

Because now, of course, it's not the only school shooting we know by name.

Sandy Hook, Parkland, Virginia Tech, Yuvaldi. I'm joined today by

Meg Anderson, a criminal justice reporter at NPR. Meg, you helped cover the Parkland tragedy.

I did. And others. There have been more than 400 school shootings since Columbine.

And there's a familiar rhythm to it all. We learn the victim's names. We try to find a motive.

Some people offer prayers, others push for gun control, and not a lot changes.

It's quiet for a while, and then it all starts again.

But from the seemingly endless cycle, a multi-billion-dollar industry has emerged. There's a long list of things schools can buy to try to deter a mass shooter, from drones to

body armor, and business is booming. This is the indicator from Planet Money.

I'm Waylon Wong.

And today we're going to take a look inside the school shooting industry.

What's for sale?

Whether these products can actually prevent school shootings

and the psychology behind the growing industry.

So over the summer, I was at this conference put on by the National Association of School Resource Officers.

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