Kiehl's skin care company's six-day LifeRide for amfAR raises money for AIDS research. The former star of "Saved by the Bell" is participating in the last three days of the ride starting Thursday - from Boston to New York City.
For Gosselaar, an avid motorcyclist, the event was a no-brainer.
"Setting a good example for my kids and leading by example is very important to me," said the father of two.
His love of motorcycles started young with his older brother Mike, a well-known motocross mechanic, teaching him to ride at age 3. Mark-Paul was competing in motocross races by the time he was 5.
The actor said in a Tuesday phone interview that he's passed the passion onto his children, Michael Charles, 7, and Ava Lorenn, 5.
"My son was riding by the time he was five," said Gosselaar. "I have pictures of me with him in a BabyBjorn, and I'm on my motorcycle, and that's the way that he would go to sleep. I'd ride around on my property at five miles an hour, but it was the noise and the wind that would put him to sleep."
Gosselaar is best-known for playing the precocious, bleach blond high schooler Zack Morris in the teen comedy "Saved by the Bell." It aired from 1989 to 1993. Fans continue to tell him how much they miss the show.
"I think what they're really trying to say is `I miss the days where, the innocence of the days where you were watching it.' But not the show, because it's still on. It's on every channel, every morning and it's been on for the past 15 years ... How could you possibly miss it?" Gosselaar said.
He said even his kids watch "Saved By the Bell."
But the 37-year-old insists a reunion special isn't likely.
"I've always thought that it would come off as a bit too corny, and I don't want to put that sort of color onto `Saved By the Bell.' I mean it's great for what it was," he said.
Gosselaar's offbeat legal comedy "Franklin & Bash" was recently picked up for a second season on TNT. Breckin Meyer co-stars in the series about a pair of ambulance-chasing attorneys who will do anything for their clients.