We all know that before Kendra Wilkinson moved in with Hugh Hefner and became one of his girlfriends, she was a super athletic kid who loved sports, namely soccer. Perhaps the reason she loved kicking the ball around so much was because she was seriously crushing on her high school coach. "We would have to run and I'd purposefully be the last because he would be there behind me," Wilkinson shares in an upcoming episode of "When I Was 17."

Check out this sneak peek from Saturday's show, where Kendra's friend confirms that she even stuck out her chest to catch the stud's attention -- plus tune in at 11/10c to find out why Asher Roth thought he was a threat to suburbia and how Kelly Osbourne feels about having dropped out of high school.

It's hard to imagine that "American Idol" winner Jordin Sparks might not have been discovered if she hadn't been chosen as a contestant. So what was the singer/songwriter up to when she was 17 (besides, ya know, winning the sixth season of the mega-popular talent show)? She was in school, annoying teachers by flaunting her vocals in class. "I always wanted to be out singing. I would be reading the assignments and singing," Sparks says in an upcoming episode of "When I Was 17."

Check out the sneak peek below, where she describes herself as a loud, quirky and bubbly high school student, plus tune in this Saturday at 11/10c to learn more about Jordin, as well as to hear what former football rivals (and bandmates) Sean Foreman and Nat Motte from 3OH!3 have to say about their teen years.

Before Kelly Rowland was belting out songs like "Independent Women" and "Bootylicious" as a member of the award-winning group Destiny's Child, she was making quite a name for herself in the car insurance circuit (read: she was terrible behind the wheel!). "I was a really, really bad driver," Rowland says in an upcoming episode of "When I Was 17." "As a matter of fact, I wrecked about three cars before I finally got the whole driving thing down."

Check out this sneak peek, where her friend verifies her vehicle misfortune, then tune in Saturday at 11/10c to hear more about the songstress, plus find out what Enrique Iglesias and Stephanie Pratt were up to as teens.

It's hard to imagine that Maroon 5 frontman Adam Levine was ever without his trusty barber and ex-Hillzie Justin Bobby. ("I don't know quite how to say this -- I've got to say this delicately -- but [Justin] is the most incredible hairstylist ever," Levine shared in a previous interview with MTV.) But before the musician made it big and had the world's best groomers(?) at his disposal, he was just a flannel-sporting teen that, presumably, trimmed his own whiskers. "My hair was long and really ratty and nappy," Levine says in an upcoming episode of "When I Was 17."

Check out this sneak peek, where he talks about his wannabe Ethan Hawke chin strap, then tune in Saturday at 11/10c to hear about Kathy Griffin's first sexual encounter and Swizz Beatz' underage clubbing days.

The Holly Madison you know (and love?) is a bubbly Playboy Playmate that spends her days doing cartwheels in striped tube socks and booty shorts. Back in high school, however, her style wasn't as cheery. "Other people would describe me when I was 17 as, like, a freak or aloof," Madison shares in the upcoming episode of "When I Was 17." She adds, "I was always, like, white makeup, black lipstick."

Check out this sneak peek video, where she recalls a story about her earlier years. Unfortch, her then-boyfriend cheated on her at prom with a "potato-headed girl" (we can't help but picture this) -- dude probably feels like an idiot now.

+ Tune in to "When I Was 17" Saturday at 11a/10c, where you'll hear more about Holly, plus discover what Dwyane Wade, and Joel and Benji Madden were like as teens.

Put a smile on that special someone's face today by sharing this amazing portrait of Mike "The Situation" and his siblings from way back in the day.

+ Tune in to "When I Was 17" this Saturday at 11a/10c for more striking pics -- as well as some pretty funny anecdotes -- from Mike, Pauly D and JWOWW's teen years.

While most high school students fail miserably at executing their senior pranks, Mike "The Situation" was actually able to complete his. After rallying up a group of his buddies, they purchased a box of furry little rodents and set out to the school cafeteria. "At noon, it was time for everybody to let their mouses out into the lunchroom," the Situation says in an upcoming episode of "When I Was 17." Mouses, meeces; tomato, tomahto (we had to; we're editors). Check out this sneak peek, where he recalls the craziness that ensued, plus make sure to tune in Saturday for a very special "Jersey Shore" edition of "When I Was 17," also featuring JWOWW and Pauly D!

Years before songstress Ciara dropped her controversial "Ride" video, she was shaking her pom-poms as the captain of her high school's cheerleading team. However, she put the coveted position on hold to pursue her larger dream of becoming a major recording artist. (Good thing she had her priorities straight!) Check out the sneak peek below and listen to the singer belt out one of her fave cheer songs. Then tune in Saturday for an all-new episode of "When I Was 17." This weekend, you'll hear about Ciara's first heartbreak, plus discover what Debi Nova and New York Yankees' CC Sabathia were like back in the day.

The self-appointed Princess of Pouf might be a total glitter-rocking girly girl, but back in high school Snooki had a tomboy side and liked to play with big boy toys. "So growing up [I was] very into, like, four-wheelers, snowmobiles, snowboarding," she shares in the upcoming episode of "When I Was 17." Unfortch, it wasn't all fun and games, because gorilla hunting and risky hobbies proved to be a bad mix for her.

Check out this sneak peek below and hear the "Jersey Shore" castie relive a scary high school incident where she flipped over an ATV and got pinned underneath. Then tune in Saturday at 11/10c for an all-new episode to hear how Snooki got out of that dangerous scenario.

Can you identify with being invisible at school but super popular (or at the very least, decently favored) outside of it, like at places such as summer camp? Back in the day, three-time U.S. National Champion figure skater Johnny Weir knew the frustration well. "I was traveling a lot while I was still attending public high school, [and] I'd get back from all these beautiful, worldly experiences and then I'd just be the kid that got made fun of because I was a lot smaller than everyone else," he shares with fans in the upcoming episode of "When I Was 17."

Check out the sneak peek to hear Johnny relive an embarrassing memory of getting tangled up in a bigger student's backpack, plus make sure to see the new episode (also featuring Jackson Rathbone and Keri Hilson) this Saturday at 11/10c.