Members of the Richfield and Academy of Holy Angels Trap Team pose for a portrait before competing at the annual trap shooting championship in Alexandria, Minnesota on June 13, 2018.

Pop. Pop. Pop. At the Minnesota high school trap-shooting championship, more than 8,000 students from some 300 schools gathered in June to blast flying orange discs out of the sky. Over nine days, the sound of bullets firing—hour after hour after hour—-becomes ambient noise, like a supermarket soundtrack. Pop. Pop. Pop.

RVs filled the parking lot. Sponsor tents (the U.S. Army, Friends of NRA, a guy selling Donald Trump T-shirts) lined the Alexandria Shooting Park, a grassy stretch in a lake-dotted region around two hours northwest of Minneapolis. Kids in their team uniforms formed a rainbow of red, orange, green, maroon, all shades of blue. Their shirts bore the names of their scholastic trap-shooting squads and the local outfits that support them. For Crosslake Community School, the list includes a local bank, an insurance broker, the American Legion and Grandpa’s General Store.

Watch: Meet the High School Trap Shooters

The Minnesota State High School Clay Target League championship bills itself as the largest shooting sports event in the world. With the bustling crowds and flood of corporate interest, it could be mistaken for, say, a scene on the NASCAR circuit, except that the stars are teenage boys and girls. And they’re armed. That’s the entire point, of course, in a shooting competition, but there are moments when the world beyond scorecards and ear protection edges into view. Bernie Bogenreif, coach for the Roseville Area High School trap team, detects one such instance as competitors from another school line up for a team photo: a couple of dozen kids arranged, shoulder to shoulder, guns in hand.

“Bet that one isn’t going in the yearbook,” -Bogenreif quips.

Then again, it might. In much of the country, the words guns and schools do tend to go together more often in horrific headlines than under a senior portrait, wedged between Class Treasurer and Spring Track. But more and more yearbooks are marking competitive shooting as a part of high school life. Even as mass shootings have inspired protests and walkouts in many schools, a growing number—-sometimes the same schools—are sanctioning shooting squads as an extracurricular activity. In 2015, for example, 9,245 students, in 317 schools across three states, participated in the USA High School Clay Target League. Since then, participation has spiked 137%: in 2018, 21,917 students, from 804 teams in 20 states—-including New York and California, as well as Texas—competed.

The uptick reflects at least two complex and relentlessly challenging realities—guns in America and adolescence. On one level, high school shooting teams weave themselves into the national debate over firearms. The NRA has funded these programs. From 2014 to 2016, the latest three years for which the NRA Foundation’s tax returns are publicly available, the organization provided more than $4 million in cash and equipment grants to schools and organizations that support scholastic sports shooting. The support dovetails with the group’s original emphasis on gun safety and training. But it also aligns with the NRA’s transformation into a political power-house that frames firearm ownership with a defiant cultural conservatism. There’s a reason Barry Thompson, a service engineer for medical equipment who has a lifetime NRA membership, helps coach the East Ridge High School team. “I’m upfront with the parents,” says Thompson, 59. “I am out here with an ulterior motive. These kids will be voting.”

Sydney Gilbertson (18) from Waconia, Minnesota poses for a portrait after competing. Over 325 high school teams attend the annual trap shooting championship. Sarah Blesener for TIME

Gun critics see the issue the same way. “Anything the NRA is for I’d say might not be beneficial for society,” says Linda Rosenthal, a Democratic state assembly member from New York City. “It’s beneficial for NRA influence and the propagation of gun use.” Rosenthal has proposed legislation banning public-school teams in her state, which are becoming more popular: in 2018 alone, participation in the New York State High School Clay Target League tripled, to 1,149 students and 59 schools. The lawmaker notes that Nikolas Cruz, charged with killing 17 students and staff members at Marjory Stoneman Douglas High School in Parkland, Fla., was a member of his high school rifle team.

“If parents are interested in their children learning about marksmanship, they have every right to send their kids to such a program,” says Rosenthal. “However, schools are places of learning. They are not places to learn how to become tomorrow’s mass shooter.”

No scientific research, however, shows that joining a shooting team makes you more likely to do harm with a gun. And there is no shortage of anecdotal evidence, at least among shooting teams, that describes such structured activities as an antidote to the afflictions often attributed to students who have carried out school massacres, including alienation and social isolation.

Sydney Gilbertson joined Waconia High School’s trap team when she was just 13. Her older brother was a shooter, but she was the only girl on the squad. “It took me out of my bubble,” says Gilbertson, 19, now a freshman at the University of Minnesota. “I owe my confidence to trap. It’s the best thing I did in high school. If this were taken away from kids … I don’t know what I would have done.” Her eyes nearly fill with tears. “I’m attached to it.”

For about a third of USA High School Clay Target League participants, trap shooting is their sole sport. “Whether you’re out in the country or close to the city, there is just a whole group of kids that need something to be part of,” says John Hanselman, the head coach at Spring Lake Park High School in Minnesota.

It’s an individual sport, like wrestling, that also offers the bonding and interdependence of a team. There are no cheerleaders, though, and the gear—-protective glasses, earmuffs, baggy vests with huge pockets—keeps the emphasis resolutely on performance. Hand-eye coordination and focus matter more than physical conditioning. Stars can emerge from anywhere.

Students from Tri-City United High School stand for the Pledge of Allegiance early in the morning on June 15, 2018, before beginning to compete in the annual trap shooting championship in Alexandria, Minnesota. Sarah Blesener for TIME

“You can take the biggest jock in high school—he can go out for high school trap and he can do good,” says LeRoy Van Brunt, committee chairman of the South Metro chapter of the Friends of NRA in Minnesota. “But you can take—and this isn’t politically -correct—the biggest computer nerd in school, or any of the girls, and they can beat that guy. And they do.”

In trap shooting, a machine known as the trap launches a clay target, or “pigeon,” into the air. Each competitor takes a hundred shots at the pigeons. Logan Gile of tiny Lakeview High School had torn his ACL, which ended his football career. He’d also torn his meniscus, which kept him off the basketball court. But the senior still found athletic perfection. At the state championship he hit all 100 of his targets, setting off a tearful celebration with his parents.

Meanwhile, Taylor Laumann, a senior at Watertown–Mayer High School who uses a wheelchair because of a spina bifida condition, fires away alongside her teammates. Thanks to trap, Laumann has earned a varsity letter. “When you have a child with special needs, some of those things you don’t really think are going to happen,” says Susanne Derner, Laumann’s mother. “She’s like the other kids, doing sports in school.”

Students participate in a pull-up challenge offered by the "Go-Army" vendor tent at the annual trap shooting championship. Sarah Blesener for TIME

Students from Eyota practice shooting before competing at the trap shooting championship. Sarah Blesener for TIME

Minnesota is a hunting state; more than a third of adults own a firearm, and in rural areas, school attendance might dip significantly during the first days of deer season. But if not for the persistence of a former Minnesota adman, thousands of students would not have gotten involved in shooting for school teams. Jim Sable, now 80, retired in 2000 after selling his advertising agency. So he started spending more time at his local gun club. He knew the club was graying when someone asked him to unload targets from a semitruck, because he was one of the younger members.

To attract the youth demo to shooting sports, Sable proposed that schools form teams. At first, the sell proved difficult. In one of Sable’s first meetings with an education board, he learned a key lesson, he says. Never use the words kids, guns and schools in one sentence unless you want a predictable response: Are you crazy?

Sable, an avuncular pitchman who founded the USA High School Clay Target League and just retired as its president, refined his argument. He asked administrators to pretend, for a second, that he didn’t represent a shooting sports organization. Imagine instead that he was asking them to start an activity that causes concussions, broken collarbones and fractured legs. No way, right? He then reminds them he’s describing football.

Students from Thief River Falls take an ice cream break in 90 degree weather after competing. Sarah Blesener for TIME

Shooters from Pelican Rapids, MN, hang out together after finishing their competition. Sarah Blesener for TIME

In terms of optics, it helps that teams do not shoot on school property. They practice and compete at shooting ranges, and can’t bring firearms to school. It also helps that the clubs and other sponsors help support the squads, so shooting teams almost never tax a school’s budget. It’s also a rare sport in which boys and girls compete -together—-increasingly so. Around 18% of participants in the U.S. high school league are female, up from 4% five years ago.

As for safety: more than 70,000 students have fired 42 million shots since 2008. No one has reported a single injury, according to the league. At Spring Lake Park, coach Hanselman tells students to consume no sugar within an hour before a shoot, lest hyperactive teens grow even more jittery on the firing line. At every school in the league, students are required to earn a firearm–safety certificate to participate on the team. “We always enforce that every time you pull that trigger,” says Josh Kern, -assistant coach for Badger-Greenbush–Middle River High School, which sits some 20 miles from the -Canadian border in northern Minnesota, “you can never take that shot back.”

The politics of guns are always present, though with experience, new perspectives can emerge. Van Brunt, the Friends of NRA honcho, mentions a mother he met at a county fair two years ago; she told him that before her son started shooting for his school’s trap team, she was almost purely anti-gun. One of the coaches, Van Brunt says, shared similar conversion tales with him.

For some kids, their support for trap shooting is bound up with broader political currents. One boy at the Minnesota event wore a Keep -America -American hat; another sported a Redneck -Nation shirt with a Confederate flag. Yet another, Tommy -Schroeder—who received a lifetime NRA membership for his 10th birthday—salutes Trump for his support for gun rights and his crackdown on illegal immigration. “We have a dream too,” says -Schroeder, a sophomore at Mora High School, about 60 miles north of Minneapolis. “We don’t want them to ruin other lives.”

When, after the Parkland massacre, school walkouts were organized to press for tighter gun–control laws, most of the trap shooters chose not to participate. “The message got swamped,” says Megan Ringate, a recent graduate of Wayzata High School in Plymouth, a Twin Cities suburb. A member of the shooting team, Ringate sat out the protest. “It wasn’t about ‘We need to protect the kids,’” she says. “It was, ‘We’re anti-Trump.’”

Another student, Logan Kluever, joined the walkout at his school, Worthington High School in the prairie flats of southeastern Minnesota. But he came to regret his decision. “I thought it was going to be a memorial for those who lost their lives,” says Kluever, 17. “I got out there, and everyone was talking about trying to get guns banned. I’d never support taking away one of my favorite things that’s passed down for generations.” He inherited a Remington 870 Wingmaster that his father bought when he was a teen.

The C-G-B Trapshooting team lines up for a team photo. Sarah Blesener for TIME

Trap shooters know that not everyone has the same perspective, even in the hallways of their schools. Fellow students, they say, sometimes view them with suspicion. Ringate has noticed it in suburban Plymouth. “Some people think that since I’m on the shooting team, I may shoot up the school or the town,” she says. “They see me wearing my apparel, and you get a, like, whoa.”

Rylee Rose, an eighth-grader who shoots a 20-gauge Remington shotgun for Spring Lake Park, just north of Minneapolis, says others grow somewhat “nervous” around her. How can she tell? “If I have my teamwear and stuff and it says trap and skeet, some people question what it is,” says Rose. “And when I tell them, they’re like, O.K., and then they kind of walk away.”

Her reaction? “I just kind of shrug and just keep walking,” she says. Back to the trap. She’s more concerned with her score.

Write to Sean Gregory at sean.gregory@time.com.