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Olivia Newton-John — who passed away on Aug. 8, 2022, after a decades-long battle with breast cancer — was nervous to play Sandy in the 1978 movie musical "Grease." Why? "I worried that at 29, I was too old to play a high school girl," she told The Telegraph in 2017. But audiences bought it and Olivia became a household name. To mark what would have been her 74th birthday on Sept. 26, 2022, join Wonderwall.com as we take a look back at more actors and actresses who were far older in real life than the school-aged characters they played on screen.
Keep reading to find out which other TV and movie "teens" were actually well beyond their years...
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In "The Amazing Spider-Man," Peter Parker was a high school kid by day and Spider-Man by night. Andrew Garfield took on the role and sold it with his boyish good looks. Still, he was 28 when he played Spidey in 2012 and 30 when he starred in the sequel two years later.
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Darren Barnet landed his breakthrough role — high school hottie Paxton Hall-Yoshida — on the Netflix comedy series "Never Have I Ever." The Los Angeles native was far removed from his high school days, though — he was 29 when the show premiered in 2020.
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Bianca Lawson starred as high school student Maya St. Germain on "Pretty Little Liars." In real life though, Bianca's school days were long behind her. In fact, she was 31 when the show premiered in 2010. She also played high school-aged students on "Dawson's Creek," "Buffy the Vampire Slayer," "American Horror Story," and, of course, "Saved by the Bell: The New Class." In other words, she was a high school student for more than 20 years.
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"Dear Evan Hansen" takes on the sensitive topic of teen mental health, but many critics have taken issue with one distracting fact: Star Ben Platt was actually 27 when he played the titular high school kid in the 2021 film. However, he was in his early 20s when he starred in the original Broadway musical.
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Stacey Dash's "Clueless" character Dionne Davenport was funny, feisty and oh-so-fashionable in the 1995 flick. Dionne was 16 (who can forget when she was learning to drive?!). Stacey, though, was actually 28 at the time. She also later joined the "Clueless" TV series and reprised the role. By the time she was done, she was 32.
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This is a tricky one. In 2002's "Catch Me If You Can," Leonardo DiCaprio acted like he was a substitute teacher, a pilot, a doctor and a lawyer. Remember, though, that he was actually portraying scam artist Frank Abagnale Jr., who started a life of crime at 17. So Leo was supposed to be 17 in the film, but the future Oscar-winning actor was actually 28 in real life at the time.
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In 2008, The CW rebooted "90210" and tried to recreate the magic of the original, "Beverly Hills, 90210." One of the main characters, Teddy Montgomery, was supposed to be about 17. He was portrayed by actor Trevor Donovan, who was 29 during his first season on "90210."
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Alan Ruck personified teen angst as Cameron Frye in the hit 1986 film "Ferris Bueller's Day Off." He always seemed a little bit more mature than Ferris and a little more grounded. He should have been — Alan was 30 when he played Cameron.
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Jason Earles played the titular pop star's annoying teenage brother on "Hannah Montana." But he almost could have played her dad. Jason was 13 years older than star Miley Cyrus. He was 29 when the Disney series, which portrayed him as a 16-year-old, debuted. He was 34 when it ended. In real life, he had a wife and a child while playing a teen.
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Monique Coleman portrayed brainy and beautiful Taylor McKessie in 2006's "High School Musical," but she was eight years out of secondary school when the film premiered.
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The cheers and chants of "Bring It On" never got old. But one of its main stars was definitely older: Gabrielle Union was 28 when she played Isis, Kirsten Dunst's character's cheer rival. In other words, Gabrielle was a decade removed from high school when she played a high school student in the classic film.
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The Fonz was wise beyond his years, and we know why. Henry Winkler, who played the iconic Arthur Fonzarelli on "Happy Days," was actually 29 when he started portraying the high school dropout. Obviously, the Fonz got older on the show, but so did Henry, playing the character well into his 30s.
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On "Beverly Hills, 90210," Andrea Zuckerman always seemed just a bit smarter than her West Beverly High School classmates… and for good reason. Gabrielle Carteris, the actress who played Andrea, was 29. By the time Andrea graduated high school, Gabrielle was actually 32 years old.
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Stockard Channing played Rizzo in "Grease" when she was 34. She was actually on her third husband in real life at the time. No kidding!
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Ian Ziering went to high school twice — once in real life and once on "Beverly Hills, 90210." Ian was 26 when he began playing Steve Sanders. He was 36 by the time the show came to an end.
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In 1994, a 23-year-old Jared Leto brought rebellious high school heartthrob Jordan Catalano to life on ABC's "My So-Called Life."
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Vote for Pedro? Pedro should have been running for Congress or city council, not school president! Efren Ramirez (right) was 31 when he played high school student Pedro in "Napoleon Dynamite." Yeah, in real life, Pedro was more suited to teach the classes than sit in them.
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Jon Heder was eight years removed from high school — and a married man — when he portrayed the 16-year-old title character in "Napoleon Dynamite." The actor's age isn't the only surprising thing about the 2004 cult classic: Jon initially only received $1,000 for his work in the indie comedy.
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Moaning Myrtle, the Hogwarts student who became a teenage ghost in the "Harry Potter" series, was played by Shirley Henderson, who was 34 when she took on the role. In fact, she was the oldest actress to portray a child-aged character in the films.
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The late Cory Monteith was 27 when he began playing Finn Hudson on "Glee." Interestingly enough, he was only four years younger than co-star Matthew Morrison, who played a teacher. Cory was still on the show when he tragically passed away in 2013 at 31. At that time, his character was 19.
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Much like his fellow "Grease" co-stars, John Travolta was not a teenager when he made the hit film in 1978. In fact, John was 24 when he played teenaged T-Bird Danny Zuko.
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Cordelia was a high school cheerleader on "Buffy the Vampire Slayer." Charisma Carpenter, the woman who played her, was 27 when she started out in the role.
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Chase Stokes was no longer a teen when he landed the role of John B on "Outer Banks." The Maryland-born actor was 27 when the first season aired on Netflix.
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When Julia Stiles starred as a high school student in "Save the Last Dance," she was pretty fresh out of high school in real life. Her co-star Sean Patrick Thomas, however, had graduated about 12 years before. Sean was 30 when he starred as Derek, the high school pal who helps Julia's character learn hip-hop dancing. Sean, by the way, also played considerably younger characters in "Can't Hardly Wait" and "Cruel Intentions."
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Taylor Kitsch went back in time to play a high school football star on "Friday Night Lights." In reality, he was 28 when he portrayed Tim Riggins. In the NFL, that's toward the end of many players' careers.
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Troian Bellisario was 25 when she started playing 18-year-old Spencer Hastings on ABC Family's "Pretty Little Liars" in 2010. The actress continued on in the role for the next seven years.
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Noah Centineo became "The Internet's Boyfriend" after sending fans into a frenzy when he starred as charming high school student Peter Kavinsky in 2018's "To All the Boys I've Loved Before." Noah was actually 22 when the rom-com came out.
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Ian Somerhalder was 31 when he landed the role of teenage Damon Salvatore on The CW's "The Vampire Diaries" in 2009. Technically, Damon was 145 years old (vampires are immortal) but was only 17 when he was made into a vamp. In real life, Ian was 37 by the time the show ended.
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Jennifer Grey might have played "Baby," but she certainly was not one! The actress was 27 when she won the role of Frances "Baby" Houseman in 1987's "Dirty Dancing" opposite Patrick Swayze. Jennifer also played a considerably younger Jeanie Bueller in "Ferris Bueller's Day Off" one year earlier.
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Keiko Agena was more than a decade older than her character, Lane Kim, on "Gilmore Girls." The Hawaii native was 27 when she began playing the 16-year-old high school student in 2000.
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When "The O.C." premiered in 2003, Benjamin McKenzie was far removed from his high school days. Nevertheless, the 25-year-old actor was cast to play teenager Ryan Atwood on the hit FOX series.
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Rachel McAdams was 25 when she played 16-year-old Queen Bee Regina George in 2004's "Mean Girls." She's actually eight years older than co-star Lindsay Lohan, who played Regina's high school rival, and just seven years younger than Amy Poehler, who played Regina's "cool" mom in the movie.
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Harry Shum Jr. was an absolute delight on "Glee." He was 27 when he originated the role of Mike Chang, which he played for six seasons.
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Tammin Sursok was almost 27 when she started playing Siena, Jackson Stewart's teenage girlfriend, on the Disney Channel's "Hannah Montana" and teenager Jenna Marshall on ABC Family's "Pretty Little Liars" (pictured).
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Michael J. Fox was 24 when "Back to the Future" hit theaters in 1985, but his character, Marty McFly, was 17. By the time Michael finished the three-film series, he was 29.
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Emily Kinney might look like a teen, but she's actually much older. The "The Walking Dead" actress was 25 when she started playing 16-year-old Beth Greene on the hit AMC show.