"All I remember is standing there and then being in the nurse's office," Gall said.
"I was terrified," said his mother, Jean Gall. "If that fracture had been any deeper, he would have paralyzed his facial nerve."
Gall had to be airlifted to a regional trauma center and only later did his parents learn from hospital staff that his concussion was likely a result of the choking game. Even Gall's little sister, 12-year-old Maggie, admitted it was a popular game among some of her peers. "If they like the buzz it gives them, then they do it again and again," she said.
The Galls believe they were lucky, because their son survived. At worst, his injuries will cost him the upcoming football season. Wanting to warn other kids, Derek said, "Even if you're curious to do it, don't do it."
Maggie Gall said she partially blamed YouTube for the spread of the game. "If kids are doing stuff on the Internet that is teaching other kids to do really bad things to themselves, then YouTube should take off those videos and not allow them on anymore. ... It's not OK."
YouTube users upload 60 hours of video every minute, and the website counts on users to flag videos that break the site's rules. In a statement to "Nightline," a spokesman for YouTube said, "The safety of our users is important to us, and as such YouTube's Community Guidelines prohibit videos intended to encourage dangerous activities that risk serious physical harm. We routinely remove material according to these guidelines, and we encourage users to flag video for our attention so that we may continue to do so." YouTube removed several links provided to them by "Nightline."
"[YouTube is] making access to an incredibly dangerous practice," said advocate Judy Rogg.
No reliable national data exist as to just how many kids have lost their lives to the choking game. Rogg said statistics are scanty, in part, because there is no education about the practice and there is no death code for when kids accidentally kill themselves this way.
"They're often misclassified as suicides," she said.
Since the death of her son, Rogg has channeled her grief into action and developed a school curriculum on the choking game to spread word of its dangers to kids, parents and educators.
"It's such a silent epidemic," she said.
Rogg is currently working with schools in Southern California and hopes school districts throughout the country will start addressing the choking game, openly. Despite a number of deaths, Rogg said she is sometimes met with resistance.
"This is a very provocative topic that people are terrified to talk about," Rogg said. "It has the same stigma that trying to get drug and alcohol education into the schools had many years ago. When I went to school, they didn't teach about drugs and alcohol. And it was, 'If I tell them, they might try it.'"
Rogg said parents are fooling themselves if they think their kid doesn't know about the choking game, or won't come across other kids who do. "Even smart, strong kids make dumb choices with deadly consequences," she said.
While her son is gone, Rogg has made it her mission to make sure this deadly game won't kill someone else.
"He was on top of the world. He felt invincible. He had no clue what he was doing. He really had no clue," she said. "It kills me."