In February a transgender boy made national news when he was forced to compete in the girls’ category, for the state wrestling championship in Texas. His case put the spotlight on the rules of all state school athletic associations, regarding transgender athletes at the high school level.

Who plays with whom? There is no standard. Rules differ from state to state -- and vary from the high school level all the way up to the Olympics.

For example, Chris Mosier is a member of the USA men’s duathlon team -- a transgender male competing at the highest level of his sport.

In Illinois, Alex Singh, who is also a transgender male, plays boys’ lacrosse at New Trier High School in Winnetka.

But in Indiana, Brad's track and field medals from middle school sit on a shelf, while he sits on the sidelines -- unable to compete in high school.

What happened?

"I came out," said Brad, whose high school has requested that NBC5 not use his last name, "and then everything went downhill from there.”

Brad competed as a girl -- his birth gender -- in middle school. But when he entered high school, he transitioned to male.

"I knew there was no way the state would let me play on the team that I wanted to play on," he told NBC5 Investigates.

That’s simply not right, according to Mosier. “All young people should be allowed to participate in sports in the gender with which they identify,” he said.

Mosier is vice president of "You Can Play,” a non-profit organization that promotes respect and opportunity for all LGBTQ athletes. He was featured in a recent Nike commercial, and in the “Body Issue” of ESPN The Magazine. He also successfully fought the International Olympic Committee to change its policy, which now allows transgender athletes to compete.

“This is absolutely a time of changing public opinion,” Mosier said. “And what will make policies go through, or change, is public opinion.”

According to Mosier’s own website, transathlete.com, 16 states are totally inclusive for transgender athletes in high school. Illinois is one of nineteen states that go case-by-case. So far, this year alone, the Illinois High School Association has granted the okay to play to all nine athletes who have requested to compete with the gender with which they identify.

For example, last year Alex Singh played on the boys’ lacrosse team as a freshman at New Trier High School. “All the kids on the lacrosse team – they didn’t have anything to say to me. They were like ‘that’s cool, that’s chill.’”

He was just another one of the guys.

“We are taught to be accepting of people; we’re taught to be nice,” said Alex. “It wasn’t really different from any other person playing. I was just another guy playing lacrosse on the lacrosse team.”

But NBC5 Investigates has found that while transgender athletes in Illinois have access to high school sports, just a few miles away in Indiana it's a different story: Indiana is one of 15 states with no policy, or with extreme requirements for transgender athletes. Indiana high school rules state that transgender athletes must show that they’ve had surgery to change their genitalia, or that they have undergone three straight years of hormone treatment.

That creates a kind of catch-22 for many transgender teens like Brad, who would have had to begin treatments as young as sixth grade, in order to be eligible for team sports by the time he entered his high school. As it is, he didn't start hormone treatments until after he began school, so he would not be eligible until his senior year -- if at all.

“My principal had basically said, ‘If I could change this, I would,’” he said.

Requiring surgery or hormone treatments doesn't make sense to Dr. Lisa Simons, a pediatrician with the Gender and Sex Development Program at Lurie Children’s Hospital in Chicago.

"Those surgeries are – A -- not desired by many transgender people, and – B -- inaccessible” said Simons.

She says hormone treatments can cost tens of thousands of dollars -- making it unaffordable for some transgender patients. They also aren't advised until high school, if at all – running into direct conflict, again, with that portion of the Indiana rules.

“Genitals don’t make gender" Simons said. "Those policies are really flawed.”

In an email to NBC 5 Investigates, Indiana Athletic Association Commissioner Bobby Cox said he did not know how many transgender athletes are in Indiana, because his organization does not keep count. And, he added, the IHSAA has no plans on addressing or changing its policy anytime soon.

That leaves Brad feeling completely banned from sports. “I can't get surgery until I'm eighteen. It's not allowed,” he said. “So it was kind of like, ‘So they don't want me to play at all.’”

After Mosier successfully lobbied the International Olympic Committee to change its policies, he said the I.O.C. came to the conclusion that requiring surgery for a transgender athlete to play could amount to a violation of the person’s human rights.

“So a transgender athlete could participate in the Olympics potentially, and not be able to play in a high school game in the state of Indiana," Mosier said. "It's ridiculous.”

For Brad, it's denying him the basic opportunity to play a sport and bond with others. He just wants to play:

"There’s no stronger friendship than being on a team with somebody,” he said, “because you get that bond; you get the bus rides; you get the long meets; you get time spent with each other, and you get to watch your friends succeed in the things that they do, while they’re watching you succeed in the things you do.

“Being on team is, like, one of the greatest friendships you can ever have," he continued. "When I found out that I wasn't able to be on the team anymore, I was like – ‘ouch.’ Yeah. It hit me pretty hard."