After his crash on the MegaRamp, Jett Eaton was airlifted to the Level 1 trauma center in Fresno, 130 miles away. “I thought I lost him,” Geoff Eaton told me recently. Jett suffered a fractured skull, bruised frontal lobes, a seizure and a concussion. When he left the hospital three days later, it was not clear if he would ever skate the MegaRamp again.

As a young child, Jett wanted to do motocross. His father discouraged that and steered him toward skateboarding, which Jett took up at 7. As his skating improved, Geoff built an increasingly elaborate skating facility near their home in Arizona and staffed it with elite coaches. Jett placed fourth in a major competition when he was 13, the age at which he was first invited to the X Games.

When I sat down with him, he had just finished a three-hour skating session. His T-shirt, from DC Shoes, one of his sponsors, was drenched in sweat. His left forearm was encased in a black cast for a broken wrist. I asked him why he kept at it, despite all the injuries. Jett says he has had about 10 concussions and five seizures, has broken six bones and has had his spleen punctured twice.

“I got my first skateboard for Christmas when I was 7, and my dad built me a small ramp in my garage, and ever since I’ve loved it,” he said. “I couldn’t stop getting on my skateboard.” On good days, skateboarding is pure happiness. “And even when I’m feeling down or not skating too well, if I start skating with my friends, I can get pumped up that way.” At the end of his workout, I saw Jett finally land a trick he struggled with for weeks, the “backside 180 nose grind” — in which the front truck of a skateboard slides along a curb — and his whole body went slack with satisfaction. His friends rushed up, and everyone exchanged fist bumps.

I asked Jett, who has returned to skateboarding’s second-largest ramp, the “mini mega,” if he will go back to the MegaRamp too. “Most likely I’ll get back on it,” Jett said.

His father is O.K. with that. “That’s his choice, if he wants to do it again,” Geoff says. “I’ll never tell him no.” He sees how hard Jett skates: five hours a day, five days a week. Some people might regard his parenting as crazy — even criminal. But where others may see only the injuries, Geoff believes he has helped his sons, now 16 and 14, find passion, identity, tight-knit peer groups. He says they eat right, sleep well and disdain alcohol and drugs. They apply the grit they’ve acquired through skating to their schoolwork.

“If you’re going to live, you can’t live behind a stop sign, taking no risk, and every time you want to do something that gets your heart beating, you decide that it’s safer if you don’t,” he says. “That’s not how I live. I don’t want my kids living like that.”