TROY, Mo.—In a cramped, carpeted amphitheater in the basement of Troy Buchanan High School, 69 students are waiting to die.

“You’ll know when it pops off,” says Robert Bowen, the school’s campus police officer. “If you get engaged with one of the shooters, you’ll know it.”

“When you get shot, you need to close your fingers and keep ‘em in,” adds Tammy Kozinski, the drama teacher. “When the bad guy and the police come through, they’ll step all over you, and who will be saying they’re sorry?”

“Nobody!” the students cry in unison.

This isn’t a bizarre, premeditated mass murder or some twisted sacrifice led by a student cult. These are the 20 minutes preceding an active shooter drill, the 13th one Missouri’s Lincoln County school district has staged in the past year.

All but 69 students have gone home for the day on early dismissal. These volunteer victims, mostly culled from the school’s drama class, are outfitted in fake-bloody bullet wounds, still wet and dripping down their foreheads, necks and chests. Bowen tells them what to expect: They’ll see “bad guys with AR-15s” shooting blanks during a simulated “passing period”—the moments when one class ends and the other begins. PVC pipes will be dropped on the floor to approximate IEDs. Crystal Lanham, a baby-faced freshman with long, gently-crimped brown hair, receives the dubious honor of being chosen as one of the gunmen’s hostages. She’s thrilled.

“I just really wanna get shot,” she jokes. “Is that weird?”

Before a school shooting simulation at Troy Buchanan High School, students Lauren Timmer, right, and Nick Guyot, use stage makeup to create fake wounds. Jim Seida / NBC News

In the wake of mass shootings from Columbine to Sandy Hook to many in between, schools have devised new and creative ways to prepare for tragedy. Most have adapted some form of the standard lockdown drill, but some districts have gone further, with programs teaching kids self-defense, proposals to train teachers with firearms—and full-scale drills like the one that’s about to happen in Troy, a town about an hour northwest of St. Louis.

In Missouri, it’s not only a trend; it’s the law. In August 2013, the state legislature took a cue from a handful of post-Sandy Hook lawmakers, like the ones in Illinois and Arkansas, and voted to require every school district to conduct simulated shooter drills. Because the law goes into effect this year, 20 superintendents from across the state are here to take notes.

Back in the drama room, the energy is jovial and jittery. Some kids, like Lanham, have never participated in a drill before. Others are veterans of simulations staged with high school volunteers in nearby elementary and middle schools (after the younger kids have gone home). Lanham is visibly excited, but some students, like 17-year-old Alex Bargen, are a little on-edge.

Stage makeup helps Troy Buchanan High School students create fake bullet wounds as they prepare to play victims for an active shooter drill. Jim Seida / NBC News

“I’ve done this like 10 times, and it gets me every time,” says Bargen, who agreed to do the drill as extra credit for drama class. “This one is even scarier because it’s on my home turf. It’s going to make me second-guess my school.”

“It’s a bit nerve-wracking because I’m disabled and can’t really run away,” says Katie Ladlie, 15, who is in a wheelchair. Her plan is to go into the elevator to the third floor and either slump in her wheelchair or fall out of it when the gunman shows up.

Kiera Loveless, 17, who has done eight drills before, “thought it would be fun at first. Now I wouldn’t say fun exactly—it’s scary. But a good experience.”

Loveless signed up because she thought it would look good on college applications. The first time she participated, she was “terrified.” She’d only heard gunshots on television. “I didn’t even really have to pretend. I kept having to remind myself ‘this isn’t real, this isn’t real.’”

Once the drill starts, Lanham and her friend, Jacob Erlitz, camp out near the bathroom. Pretty soon, a group of students sprint down the hallway screaming, just as a piercing fire alarm goes off. Seeing the gunman up close, Lanham realizes it’s Bowen, the same man who was giving us instructions a few minutes before. He “shoots” Erlitz and takes Lanham hostage as promised, barking at her to bang on classroom doors and urge the occupants to open them.

“Someone let me in!” Lanham shouts. She isn’t smiling anymore. “Somebody, anybody, open the door!”

None open.

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During the active shooter drill, student actor Josiah Zimmer runs past school faculty while another student plays dead on the floor. Jim Seida / NBC News

The energy blast from the guns has filled the hallway with dust from the ceiling tiles and the scent of gunpowder. Bullet shells litter the floor. After several excruciating minutes, a few cops run down the hallway, and when one aims at the gunman, it’s all over.

It’s been eight minutes and one second. The intruder has been “engaged”—the officers’ fancy word for “killed.”

Student actors portraying shooting victims lie on the floor. Jim Seida / NBC News

There are several kids splayed out in the hallway, their fake blood still glistening. The kids start to rise, most nervously tittering, a few picking up shells as souvenirs. One girl, who has fallen on her stomach after getting “shot,” doesn’t get up. Her body is trembling. It doesn’t take long to realize she is sobbing.

After the active shooter drill, Troy Buchanan High School sophomore Alexis McCourt wipes away a tear. Jim Seida / NBC News

The Lincoln County School District has been holding drills since September but didn’t always include students. The drills, after all, aren’t really for kids—they’re meant to help law enforcement craft strategies to take down active shooters, as well as to familiarize teachers with the sound of guns and teach them to act quickly. The first drill, also at Troy Buchanan High School, simply consisted of teachers lined up in the hallway as an “intruder” shot blanks in front of them.

But it felt stilted and staged. “We figured, ‘we’re not really doing anything,’” says Lieutenant Andy Binder, who helps coordinate the simulations. The drills have since become more spontaneous, and kids were eventually added, Binder says, to ramp up the realism for the teachers. This drill had the most students by far.

“We’re beginning to see what we’ve done wrong and right,” says Binder. “The first time…it took us about two and a half minutes to engage the shooter [once we entered the building]. Today it took 30 seconds.” During another drill, the teachers were told to call 911 from classroom phones, only to discover that they had to dial “9” first to get an outside line. That was swiftly corrected.

And even though they’re mostly there as props, the students learn strategies, too, says Binder—like not hiding in bathroom stalls, since automatic toilet flushes may give them away. That Wednesday, most kids seem to agree it was worthwhile. Even the girl who was shaking and crying, 15-year-old Alexis McCourt, says she “doesn’t regret it at all."

“It’s so hard to hear all of [those gunshots] and not freak out,” she says. But “I’m actually happy I did do it because now I know what some of the kids who came out alive in Sandy Hook felt.” If there is a shooting, she says, she’ll be prepared and “not just stand there.”

But not everyone felt invigorated. Amy Venneman, who teaches English, says having the student actors there ratcheted it up to a different level. “When I saw all the kids just running and screaming down the hallway, it really hit home for me,” she says.

During the drill, Venneman heard Lanham’s pleas to let her in, and she thought, What do I do? I’m supposed to keep the door shut, but I hear another student out there. “It made my heart hurt immediately,” she says.

The experience left Venneman feeling ambivalent.

“You want kids to feel like school is a safe place to be,” she says. “And I know those kids chose to be there, but for it to be that realistic, that’s almost too much. As a parent, I wouldn’t want that many kids being terrified, just knowing my own reaction to it.”

“It’s so hard to hear all of [those gunshots] and not freak out."

Other Missourians were more unequivocal about their disapproval. When Wayne Johnson, a firefighter from St. Louis, found out about Troy’s drill via a writeup in the St. Louis Post-Dispatch, he tweeted the link with the comment, “B/c this is a thing, we've failed, America.” He found the photos of kids spattered with fake blood “surreal.”

“I would have a real problem with them doing that in my kids’ school,” says Johnson, a veteran of Afghanistan who recognized the “moulage” used for the students’ stage injuries. “Sure, I get it, that’s probably the best drill training that you’re gonna have, but at what cost?” He worries that the drill would “traumatize” some kids and “desensitize” others.

Of course, Johnson’s kids won’t have to volunteer, and even if they did, they won’t necessarily have the same experience as the students at Troy Buchanan. There’s a continuum of possible simulations, ranging from fire drill-like evacuations to the bells-and-whistles variety. Kenneth Trump, president of National School Safety and Security Services, thinks that “a nice happy medium is a tabletop exercise,” which instructs school staff, first responders, and mental health agencies “by Powerpoint in a classroom-type setting, discussing hypothetical situations.” (Incidentally, this model fails to hold up to the new Missouri law, which requires a live simulation.)

Trump warns against “acting emotionally rather than cognitively,” which can distract school districts and law enforcement from preventive measures like counseling services for troubled students.

And according to Stephen Brock, a California State University professor and member of the National Association of School Psychologists, those counselors may be necessary for a fake shooting, too.

“Live drills can be very intense and potentially psychologically harmful for some people,” says Brock. It’s not likely to cause post-traumatic stress on its own, but “if a child has some pre-existing mental health challenges”—up to 20 percent of students do, says Brock—“this could exacerbate that challenge.”

Experts say these reactions hinge on how responsibly the drill is conducted. Across the country, the community hasn’t always been well-informed; one active shooter drill at a charter school in rural Oregon came in the form of a sneak attack that left teachers momentarily terrified.

There’s also a difference between using student actors, who are fully-debriefed volunteers, and involving all students in this kind of exercise. Cary-Grove High School in Cary, Ill., faced criticism from parents last year when they staged an active shooter drill, blanks and all, with the entire student body present. One concerned mother from Hartselle, Ala., started a petition on change.org against a planned active shooter drill that would have involved elementary school students.

“We would never do that,” says Lt. Binder. “Law enforcement agencies that do that are making a grave mistake. We’re not here to create panic or fear.”

“It made me think, you have to look at everyone as a threat. That sounds so harsh, but you don’t know anybody’s story.”

Even though the kids at Troy Buchanan don’t appear to be traumatized by the drill, many of them have adopted a verbal tic: “When it happens, I’ll know what to do.” Or, “When it comes, I won’t be frozen in my tracks.” They seem to have internalized the idea that a school shooting is inevitable—it’s not a question of “if,” but “when.”

Alex Bargen confesses he’s been stressed about it ever since “it almost happened” more than a year ago in Troy. In September 2012, a Troy Buchanan student was arrested after his girlfriend reported to law enforcement that he was planning to kill four students on his 17th birthday. The charges were eventually dropped, but the day the girlfriend reported the incident, the news spread like wildfire. It wasn’t long before people were posting on Facebook that there had been shots fired in schools (there hadn’t been).

“This drill made me think of that,” Bargen says. “It made me think, you have to look at everyone as a threat. That sounds so harsh, but you don’t know anybody’s story.”

Police officers enter Troy Buchanan High School for the active shooter drill. Jim Seida / NBC News

School shootings are indeed increasing, despite the proliferation of drills and heightened security measures. Yet the likelihood of a violent death in school is still minuscule—about a 1 in 2.5 million probability, says Brock.

“With an event that is just so unlikely, a school needs to critically assess what their drills should include,” he says. “They should ask themselves, ‘What are we going to spend our limited time and resources on?'”

But statistics aside, the headlines keep pouring in, leaving people with what Trump calls “active shooter cumulative stress”—the uneasy feeling that something bad could happen at any time.

In the aftermath of the drill, the kids reconvene in the drama room. Tissues smeared with crimson are piled up in the wastebasket. The “victims” talk excitedly, overwhelmed with emotion and assessments. They describe what it felt like to get “killed,” or where they hid, or how freaky it was to see their teachers so panicked.

One quiet girl named Haylee Martinez begins to wax philosophical about real-life shooters: “It makes me wonder, like, who these guys are who enjoy being powerful. When they hold the guns, how much power do they have over us?”

Whether they enjoy it or not, the answer is clear.

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