If the success of Netflix's Stranger Things proves anything, it's that sometimes you can actually cast teens and young adults in age-appropriate roles and they'll knock it out of the park. Most of the young adult actors on that show are actually the ages of the characters they're portraying, with the odd exception like Charlie Heaton, who at 23 is a bit old to be a high school student (well, maybe a really bad one).

Maybe this trend will spark a new era of casting, where people literally act their age, but given the hilarious usage of 20-somethings in many classic teen-driven shows, many sitcom and drama show actors will continue to play awkward, nerdy-but-only-with-glasses-on type characters who seemingly never leave high school or age whatsoever.

It's been a running joke that shows like Dawson's Creek have always had 20-somethings playing teens (James Van Der Beek was 21), and the trend is equally present in movies, such as when Shirley Henderson (36 at the time) played 14-year-old Moaning Myrtle in Harry Potter And The Chamber Of Secrets. It begs the question: Why not always use real teens to play film and TV teens? Who could understand the growing pains of those tender years better? Well, if you want a possible answer, look at Stranger Things' Dustin (Gaten Matarazzo). Cute kid, but would you really want to see him make out with anyone on the cast of Riverdale?

Stacey Dash Doesn't Age

Quick, from the photo above, how old would you say Stacey Dash is? Whatever your number was, it probably wasn't 49. Seeing as how Dash still looks like a 30-something Hollywood starlet, it's not surprising she was tapped at 28 to play Dionne Davenport, best friend to Alicia Silverstone's Cher in 1995's Clueless. The movie was a giant hit and a pop culture milestone, summing up 1990s Valley Girl culture. While she looked great in the role, it's a weird thought that someone in their late 20s was playing a literally clueless teen who almost causes a giant freeway pileup, and constantly spouts goofy California rich kid lingo. Dash pulled it off, but some other stars? Not so much ...

The Fonz Was Supposed To Be A Teen?

Henry Winkler's Arthur Fonzarelli, or, "The Fonz" as he was known on the 1950s throwback sitcom Happy Days, was an icon of cool. The guy always wore leather jackets, had perfect slicked-back greaser hair and had a seemingly unflappable demeanor. The guy even literally jumped over a shark on jetskis, so he was obviously the picture of awesomeness. He was also supposed to be about 19, which is totally hilarious considering that Winkler was pushing 30 at the time, and looked even older. This alone made the whole character awkward. He came off less like the cooler older dude hanging out near the jukebox, and more like the cool uncle who lends you his Led Zeppelin LPs, which admittedly is still pretty awesome.

Marty McFly, Eternal High Schooler

Michael J. Fox as high schooler Marty McFly in the first Back To The Future film maybe isn't that big of a stretch, what with his boyish good looks, goofy demeanor and squeaky voice. The problem is, he was 24 in the first movie, and 29 by the time the trilogy wrapped up, and he definitely looks it then. Crispin Glover, who played Marty's father George McFly, was ironically 21 in the original film, making the kid older than his father in real life. That means that Marty McFly was playing to his younger dad and also his 24-year-old mom (Lea Thompson) when he ripped through that Chuck Berry song onstage in the first movie. Someone needs to get in a DeLorean and sort this out.

Tobey Maguire's Spider-Man Growing Pains

Spider-Man goes through a lot in the reboot trilogy starring Tobey Maguire. On top of being bitten by a radioactive spider and gaining superpowers (not relatable), Maguire's Peter Parker has the usual problems of an awkward teenager, like being picked on at school (very relatable), and not always getting the girl. Thing is, Maguire was 27 when the first movie came out. Like Michael J. Fox, Maguire had the boyish looks and not-so-adult voice necessary to play Peter Parker, but nothing prepared audiences for his brief and cringeworthy turn as a dark, "sexy" bad boy in the sequel, as Spider-Man falls under the influence of an alien symbiote. Parker gained new confidence, discovered pomade, and busted out some, uh, interesting dance moves. Maguire seemed like a teenager going through a premature midlife crisis, and it was awkward with a capital A.

Smallville's Tom Welling: Not Small

Smallville lasted through 10 seasons and 218 episodes and showed an in-depth story of Kal El/Clark Kent's young adulthood on the path to becoming Superman. It tackled Supe's coming to terms with who he was, being an awkward teen, and his amazing superpowers. Apparently one of his powers was super-puberty because Tom Welling's portrayal of the character sure didn't look like a high-schooler, Welling being 24 and way too buff to be playing a 14-year-old Clark Kent in the pilot. Seriously, even among stars from shows like Beverly Hills, 90120 and Happy Days, Tom's uber-buff physique makes believing that he's at the age where even talking to girls can be awkward pretty ridiculous. But hey, Michael Rosenbaum's Lex Luthor looked to be about the intended age (early 20s) even though he was 29. If the camera adds 5 pounds, muscles add at least 5 years.

Olivia Newton-John Could Have Taught High School

In 1978's high school musical Grease, Olivia Newton-John's character Sandy is a shy, somewhat reserved teen who falls for John Travolta's typical greaser boy Danny. Again, the awkwardness here comes from the audience having to suspend their disbelief at these two VERY obviously adult actors supposedly doing homework, drinking sodas, and talking about summer crushes. Newton-John was 29, Travolta was 24, and most strikingly, supporting actress Stockard Channing was 33. Kind of makes you wonder why the "kids" in Grease didn't just drop out of school to apply for teaching jobs, at least then they'd get the summer off from having to learn those musical numbers and complex dance routines.

Keiko Agena Was Too Old To Be Listening To Her Parents

Playing supporting character Lane Kim on the WB's dialogue-heavy teen girl cult show Gilmore Girls, Keiko Agena's portrayal of the gawky 15-year-old audiophile who has to sneak her rock CDs past her restrictive parents was pretty spot on. Not bad for a 27-year-old who is 44 now. As the sidekick to the show's resident motormouth Rory, Kim was a not particularly rebellious character, once daring to dye her hair purple, only to instantly change it back when she feared her mother's opinion. Her status as a slightly awkward "Secret Rebel" made her a fan favorite, even if Agena herself never really broke through in Hollywood outside of the hit series.

Cameron's Phone Voice Explained

There's a popular fan theory that states that Alan Ruck's high school student character Cameron is actually imagining Ferris' voice in his head in Ferris Bueller's Day Off, and that Ferris is the gangly, buttoned-down teen's repressed need to rebel personified. Neat theory, but who knows. One thing that does stick out about Cameron is his character's deep voice, and seeing as how Alan Ruck was nearly 30 at the time, it's no wonder. His clean-shaven appearance and goofy grin made him a perfect fit to play the somewhat shy Cameron though, and his iconic supporting role as the nerd who finally stands up for himself made him one of director John Hughes' more enduring minor characters. Knowing Ruck's age sure explains why Cameron was so good on the phone ...

Wee-Oooh, Gary Busey's Buddy Holly

Gary Busey, Hollywood oddball, action-movie harda*s, Trump apprentice and an all-around bizarre guy, played Buddy Holly in a 1978 biopic about the classic 1950s songwriter who died tragically at 22 in a plane crash that also killed the Big Bopper and Richie Valens. Yes, that's a true statement, and on top of that Busey was nominated for an Oscar for his portrayal. Life is weird sometimes. Nothing about this should have worked, especially since Busey was 34 at the time, but his transformation (he slimmed down drastically) was shocking. He was a dead-ringer for the nerdy, awkward but brilliant Holly, a bespectacled youth from Lubbock, Texas who forever changed music. Just don't remind us about anything Busey's been in for the last 25 years or so.

Alyson Hannigan's Nerd Witch

At 23, Alyson Hannigan wasn't as big a stretch as some on this list to play everyone's favorite teen witch, Willow Rosenberg, on the Buffy The Vampire Slayer series. Although many younger TV watchers probably know her as Lily Aldrin from the sitcom How I Met Your Mother, in the 1990s Alyson was the sidekick to end all sidekicks. Her role on the show put her at the same level as Sarah Michelle Gellar's Buffy as an all-powerful dark witch, even casting her as the "Big Bad," or villain of season 6. Not bad for a character who started off as a bookish and shy introvert with a fear of ponies, and ended up being arguably the MVP of Buffy The Vampire Slayer's so-called "Scooby Gang" of heroes.

Seth Green Can't Hardly Age

Seth Green had a busy career, even co-starring with Alyson Hannigan as her long-term boyfriend Oz, who just happened to be a werewolf. Other recurring roles Seth has had are the voice of Family Guy's Chris Griffin, and Dr. Evil's son, Scott. While Seth started voicing Chris Griffin at 25, his breakout movie role came at 24, when he played the hilariously uncool high schooler Kenny Fisher (or Special K) in 1998's Can't Hardly Wait, a character who tried desperately to come off as a confident playboy but was more the type of guy who'd pass out after 2 wine coolers. Many things are unfortunate about Special K, from his so-90s-it's-painful yellow goggles to his painfully delivered slang, to his ... Everything.

Andrew Garfield: Backup Spider-Man

While not a terrible choice to play the role of Spider-Man, Andrew Garfield is no Tobey Maguire, though he somehow manages to play Peter Parker as an even more awkward, although overall slightly less endearing teenager. The fact that he was about 30 when he played ol' Webhead in the first of the 2nd reboot series, The Amazing Spider-Man, probably helped make it more awkward. The new reboot's jokes about, ahem, teenage issues help make it weird as well, for example, Peter Parker's uncontrollable webbing blasts. The series has gone on to some critical acclaim with 2017's Spider-Man: Homecoming, but sorry Andrew, you'll always be number two. Chin up, at least there's that Marvel MCU paycheque to look forward to.

Gabrielle Carteris, 9021-Old

Another "Nerd who's actually hot "a la Buffy's Willow", Gabrielle Carteris' portrayal of Andrea Zuckerman on Beverly Hills, 90210 really strained the audience's suspension of disbelief. On a show with Luke Perry, 24 at the time, and Ian Ziering, 26, Carteris was 29 when she started playing the awkward and bookish Andrea Zuckerman. In contrast to Alyson Hannigan's portrayal of Willow, Andrea is more of a go-getting honor student with aspirations closer to attending an Ivy League university than becoming a night-stalking, vampire killing mage, but whatever. Hot nerds unite!

Nicholas Brendon Is Awkward In Real Life

Another Buffy The Vampire Slayer Alum, Nicholas Brendon somehow never really caught on outside the show. His Buffy character Xander Harris was a socially inept uber-loser, who nevertheless had a witticism for almost every occasion, making him a fan favorite. However, after Buffy, in which the then 26-year-old portrayed a high schooler, Brendon's star faded a fair bit, despite some fairly recent TV semi-success. However nerdy Xander seemed on the show, whether he was hitting on girls way out of his league or getting slapped around by vampires, his real-life run-ins with the law were a whole lot more awkward. In 2010, Brendon was tased by police after responding to a drunk and disorderly call, and later that year he checked into rehab for pill addiction. More recently he's trashed hotel rooms and walked off the Dr. Phil show after being asked point-blank about his alcoholism. Here's hoping Brendon gets it together.

Jon Heder Defines "Awkward" For A Generation

Wow, where do we start with Napoleon Dynamite? The 2004 cult film starred Jon Heder in the title role, a perennial outsider with bizarre social graces, brillo-pad hair, and a shy, awkward demeanor, to put it mildly. What made the character endearing was ultimately his total lack of self-awareness and inability to repress his need to shake his butt onstage, which at long last got him the approval he lacked from his high school peers. Heder was 26 in this role, but he nailed the goofy, awkward mannerisms of Napoleon's character so well that it almost seemed like he WAS Napoleon Dynamite, or at the very least was working out some kind of teenage social trauma on the big screen. Either way, kudos to Heder for letting it all hang out, barely opening his eyes the entire movie, and letting us in on a golden truth: girls only want boyfriends with nunchuk skills.