ASPEN, Colo. — Tanner Hall made a mistake. He knows that.

The freeskiing sensation got kicked out of high school for smoking marijuana when he was a sophomore.

Hall never went back, pursuing a lucrative career on the slopes rather than a diploma.

It's a decision he still laments.

So the 25-year-old is doing something about it — heading back to school. Hall will start an intensive six-month program at a school near Heber City, Utah, to complete both his junior and senior years.

"When I get that diploma, it's going to feel like I won the X Games," said Hall, a Kalispell, Mont., native who had his streak of three straight titles in skiing superpipe halted as he finished second to France's Xavier Bertoni at Winter X on Thursday night. "I'm ready to close that chapter and move on."

Skiing has been splendid to him. He's made movies, toured remote parts of the world, even started his own ski company.

He's also found success — lots of it. He's one of the most decorated skiers in Winter X history.

But the term "drop out" ate at him.

Hall said he failed a drug test for marijuana while attending the Winter Sports School in Park City, Utah, and was expelled.

Big deal, he thought at the time. He had skiing.

Who needs an education?

Turns out, Hall did.

"That was the worst decision of my life," he said.

Hall thought about simply going for his GED — a "good enough degree" as he calls it — but wanted the real thing.

"That way, if there is a day I wake up and do want to go to college, I can actually go because I've got a real diploma," he said.

He'll soon be sitting in a classroom full of teenagers, learning pre-calculus and history, possibly even a foreign language.

Hall can't wait to begin.

"If you want to sit down with me in class all winter next year, come join me," he said, laughing.

Hall wasn't all that old when he burst on the X Games scene, winning his first gold in 2001 at 17. He has captured seven titles at the event, tying him with Shaun White for most at Winter X.

No. 8 was not to be as the 20-year-old Bertoni turned in a superb run, pulling off some difficult switch combinations to earn the win.

"It's amazing," Bertoni said of his title. "I'm going to do a big party tonight."

Hall's good friend and halfpipe nemesis, Simon Dumont, took third. Dumont had a big run planned, but had to scrub it.

"Pipe just is not long enough. If they're going to make it big, make it longer," Dumont bemoaned.

After turning in the best run during the elimination round the night before, Hall had the final run of the evening. He moved up a place, but it wasn't enough to unseat Bertoni, who finished 14th in the event last season.

"The kid was on his game," said Hall, who mixed in the double flip that he's been perfecting in practice. "I wasn't holding anything back."

That's the approach he's now taking with his education. He's going all out for the degree.

Only this time, he won't have to worry about prom, acne or being socially accepted.

"It's tough growing up as a teenager," he said. "There are so many pressures. If you're not a football player, you're a dork. If you've got zits, you're not getting the hot girl. It's a hard thing. But if you've got a passion, whether it's skiing, soccer or mathematics, chase it with full bore. You can do whatever you want in this world. I'm living proof of what you can achieve if you really put your mind to it."