Dave Thorson received a letter in the mail not too long ago. His wife handed it to him.

"AARP card," he said, shaking his head. "I thought, 'Are you kidding me? This can't be for me. It's got to be my mom's name on it.' I don't feel like I'm 50."

Doesn't act like it, either. At least not on the sideline.

He still screams 90 decibels in his raspy voice. Still turns three shades of red over a blown call. Still acts like a crazed madman over every single possession and every tiny detail in a basketball game.

He's still got a lot of juice left as basketball coach.

Thorson's DeLaSalle team made history Saturday by winning a fifth consecutive Class 3A state championship with a 79-65 victory against Fergus Falls at Target Center.

The Islanders became the first program in state history to win five championships in a row.

Their title also accomplished what the school was calling another milestone — Thorson's 500th career victory at DeLaSalle, which includes eight state titles.

And then another streak continued postgame: the annual question about why the Islanders still play in Class 3A and not 4A.

Actually, Thorson made a pre-emptive strike, posing the question to himself as he started his press conference.

He knows the drill by now.

"That decision is not the coach's decision," he said. "I'm not trying to say it's somebody else's decision. But every year at the end of the season our president, our principal and our athletic director, we have an end-of-the-season meeting and we talk about that. I don't know what's going to happen. At some point, we'll internally talk about that."

Thorson remains a polarizing figure in Minnesota basketball because DeLaSalle, a private school, hasn't moved up in class against the big schools.

Five consecutive championships and talent assembled on their roster offer enough evidence that the Islanders could handle themselves in Class 4A.

The Islanders have Division I prospects in junior Goanar Mar and sophomore Gabe Kalscheur. The Islanders play hard-nosed defense, they share the ball on offense and they're tough competitors.

They play the right way.

Thorson's sideline antics and presence in 3A earn him critics, but one thing is undeniable: The man pours his heart into coaching and he's very good at it.

"We're used to having this big target on our back," he said.

Thorson doesn't apologize for the way he does things. He's unabashed in his effusive praise for the tradition and culture at DeLaSalle.

"I guzzle the Kool-Aid," he said.

He also sells the Kool-Aid, too. He would spend 30 minutes extolling the virtues of DeLaSalle to an empty room.

"I am the worst person at being subtle," he said.

Thorson still makes his team practice at 6 a.m. every morning, even this past Friday, a day between the semifinals and championship game.

Why?

"We've been doing it for two decades," he said. "It helps develop the self-discipline that we feel ultimately will help kids later in life. I'm hoping that they will be stockbrokers. Guess what, the bell rings at 7:30 [a.m.]. You've got to be ready to go."

Thorson turned 50 in February. He's coached 22 seasons at DeLaSalle. He's got gray hair now, gray beard. He's lost 50 pounds as he's gotten older.

"I want to have that energy for those guys," he said.

Every now and then, he dreams about coaching in college. Usually hits him as he watches the NCAA Tournament in March and sees some of his coaching friends leading their teams.

"I'm not going to say that every once in a while I don't go, 'Man, I'd like to have a team in the tournament,'" Thorson said. "But at the same time, I'm able to have an impact on young people that I'm not sure I'd have at the collegiate level. That's something that's kept me at DeLaSalle this whole time."

Time and championships haven't mellowed him. He still works the sidelines like a man coaching for his next meal.

He has 500 wins now, eight championships. It would have been fun to watch this team, Thorson's 22nd, play the 4A field and see how it stacks up.

The Islanders would not have been overmatched.

Chip Scoggins • chip.scoggins@startribune.com