"He started coughing loudly. We were a little confused at first, wondering what was happening," White said.
At Millis High School, all students learn CPR in physical education class.
"We've been doing this for about 10 years. We teach every sophomore in the building," Millis High School physical education teacher Anthony Fallon said.
White took the course last year. It includes how to perform the Heimlich maneuver when someone is choking.
And suddenly in math class, someone was choking.
"I went up behind him and wrapped my arms around him. And so I asked him, like, ‘Are you choking?’ Just to make sure because I'm going to put my arms around him. He started shaking his head again," White said.
White applied five or six upward thrusts to the choking student's diaphragm and out popped a pen cap.
"At the time I was stunned for like a second, but all the adrenaline I was getting when it happened, I was able to do it without being nervous," White said.
Fallon said that is no small feat.
"It's the first time I heard one of our students react to a situation and use what we've taught them in a real-life situation, which is remarkable," Fallon said.
The Millis Fire Department thought so, too. It recently presented White with its "Lifesaver Award" for his heroic actions in December.
"I think most of the other kids were stunned, and you can't blame them for that because it was a scary thing. I was scared after the fact, he was still scared. The whole thing was crazy," White said.
In nearly 40 states, high school students can't graduate unless they pass a CPR training course. Massachusetts has no such requirement, yet. Legislation to that effect is pending on Beacon Hill.
Count White as a supporter.
"It's a skill that everyone, I think, should learn, especially in high school," he said. "You never want to have to do it, but we all wanted to make sure we knew how to do it."