Hollywood tends to cast twenty-something-year-olds to play high school students in major films and television shows. However, they have even cast actors close to or in their 30s to play the same age characters. One example includes Michael Tucci in his role as Sonny in Grease, which quickly becomes evident to viewers that he isn't in high school.

RELATED: 10 Actors That Were Unrealistically Close In Age To The Actors Playing Their Parents

The unrealistic ages of some actors playing much older or much younger characters aren't as obvious as Tucci at 32 years old playing a high school student. There could be a few actor ages that may shock fans.

10 Jason Earles Has A 15 Year Age Difference Between Him And Miley Cyrus

Jason Earles stars as Miley's brother in Hannah Montana

Disney Channel popularized many sitcoms for young children, but not every actor was still in their teenage years. Jason Earles plays Jackson Stewart, the 16-year-old older brother of Miley, in the hit show Hannah Montana. While Miley Cyrus was 14 years old when the show first aired, Earles was about to turn 30.

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Earles continues to appear in Disney Channel productions. His most recent Disney acting credit is Rudy Gillepsie in Kickin' It, a martial artist closer to Earles' actual age.

9 Stockard Channing Has Largest Age Gap Between Her And Her Character In Grease

Stockard Channing leading the pink ladies grease

Michael Tucci wasn't the only actor to play a much younger character. Stockard Channing was cast to play high school-aged Betty Rizzo, the leader of The Pink Ladies, in the hit 1978 film Grease when she was 33 years old.

Most of the cast in Grease were much older than the actual ages of their characters. However, Channing has the largest age gap of 15 years between her and her character. Jeff Conaway plays Kenickie, Rizzo's love interest, who is in his late 20s at the time of filming.

8 Moaning Myrtle's Actual Age May Be Surprising To Fans

Moaning Myrtle star in Harry Potter

This shocking age difference may be a little less obvious to viewers. While Moaning Myrtle's life was unfortunately cut short at merely 14 years old, Harry Potter actress Shirey Henderson was 37 years old during her first appearance as this moody ghost. Henderson is the oldest actress in the Harry Potter franchise to play a teenage-aged character.

She reprises the role of Moaning Myrtle in the Goblet of Fire. While Myrtle doesn't age due to her ghost status, Henderson was 40 years old at the time of that film's release.

7 Most Of The Castmembers In Riverdale Are In Their 20s

Josie In Her Band Josie And The Pussycats Playing On Stage In Riverdale

The plotline isn't the only confusing element to The CW's hit show Riverdale. Most of the show's cast members are several years older than their characters. This includes Ashleigh Murray in her role as Josie McCoy, the lead singer of Josie and the Pussycats.

At the time of Riverdale's debut in 2017, Murray was 29 years old, playing a high school sophomore. Josie transitions from being a main character in the fourth season to receiving a spin-off series titled Katy Keene, based on the Archie Comics series of the same name.

6 Andrew Garfield Is The Oldest Actor To Portray Spider-Man

Andrew Garfield in The Amazing Spider-Man

Andrew Garfield is in recent news for his praiseworthy portrayal of famed playwright Jonathan Larson in the biographical musical titled Tick, Tick... Boom! Before showing off his singing chops, Garfield plays the familiar role of Peter Parker/Spider-Man in Marc Webb's The Amazing Spider-Man. 

RELATED: Tobey Maguire Vs. Andrew Garfield: Who's The Stronger Spider-Man? 

While the actors who portray Peter Parker are frequently older, Garfield is the oldest at 29 years old, playing a 17-year-old high school student. While the Amazing Spider-Man movies may not have been well-received, Garfield's performance is highly praised regardless of the age difference.

5 Tobey Maguire Is Also Much Older Than Peter Parker

Tobey Maguire in Spider-Man 2

Another Spider-Man actor that is much older than Peter Parker is Tobey Maguire. At the time of Sam Raimi's first installment in the Spider-Man trilogy, Maguire was about to turn 27 years old. Although Maguire looks much younger than his actual age, it's easy to be unaware of a fact like this.

The age difference didn't seem to pose a big problem to viewers, as he stars in two more films in 2004 and 2007. They both became the highest-grossing films of the year they were released, and Maguire is considered the best Spider-Man by many fans.

4 Rachel McAdams Plays A Highschool Mean Girl In Her 20s

Rachel McAdams in her role as Regina George

Rachel McAdams quickly rose to fame in her role as snobbish Regina George in the cult teen film Mean Girls. While McAdams plays a high school bully, she was actually 26 years old when the film released.

Another incredibly shocking fact about Mean Girls is the unrealistic age difference between McAdams and Amy Poehler, who plays Regina George's mother. Poehler was 33 years old at the time, not even 10 years older than her daughter. It may surprise fans to find out McAdams filmed Mean Girls and The Notebook during the same year.

3 Gwyneth Paltrow Started To Date Brad Pitt During Production Of SE7EN

Gwyneth Paltrow in the movie Se7en

Gwyneth Paltrow gained notoriety for her role as Viola de Lesseps in the historical romance film Shakespeare in Love in 1998. Prior to that Academy Award-winning performance, she co-starred alongside Brad Pitt and Morgan Freeman in the 1995 film SE7EN. 

Paltrow plays the on-screen wife of Brad Pitt's character at only 23 years old, despite her character being in her mid-30s. Paltrow is nine years younger than Pitt, but actually pursued a relationship with him during production and even got engaged before calling it off and dating Ben Affleck.

2 Daniel LaRusso Was Actually In His 20s During The Karate Kid

Ralph Macchio playing Daniel LaRussio in The Karate Kid.

Ralph Macchio plays the iconic role of Daniel LaRussio in the 1984 film that started it all: The Karate Kid. Daniel is a 17-year-old high school student constantly picked on by the bullies of Cobra Kai. Macchio's short stature makes it easier for him to play younger roles.

RELATED: Cobra Kai: 5 Ways It Redeemed Johnny (& 5 It Made Him Worse) 

Thomas Ian Griffith, who plays Terry Silver in The Karate Kid Part III, is actually five months younger than Macchio, which isn't evident due to Griffith being 6'5. The Karate Kid fame continues in the sequel series Cobra Kai, which focuses on the evolution of Johnny, Daniel's bully, and some new problems that arise.

1 Michael J. Fox Is Older Than Crispin Glover In Back To The Future

Back To The Future Poster.

Just about everything Marty McFly sports in the Back to the Future films is iconic. From the puffer vest to the hoverboard. Who wouldn't think he's the coolest high school student around? However, Michael J. Fox, who plays Marty, was actually 24 years old when the first film released.

This makes him actually days older than Lea Thompson, who plays his mother, and Crispin Glover, who plays his father. Like Ralph Macchio, Fox is also short in stature and looks much younger than he is, which makes it easier for him to play roles like high school students.

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