It has been customary for a long time now to cast older actors as high school kids. Perhaps those actors are more mature, and perhaps the rest of the cast and crew don't have to deal with child-labor laws. But whatever the reason, some if not all of the casts of some of our most popular high school-based shows are all much older than their on-screen counterparts.

At this point, it might sound like a broken record, but there is seemingly a huge double standard in Hollywood, where youth is always heralded. However, the youthful characters are very often being played by someone older. Older actors are continuously playing younger characters until they're deemed too old to play much of anything.

Minka Kelly – Friday Night Lights

Friday Night Lights came along during the early days of super-crazy internet fandom, which helped it stay on the air. The critics adored it too, thanks to the show's portrayal of rural middle America and the country’s love/obsession with football. Based on the movie and the book of the same name, the show chronicled the highs and lows of High School football coach, Eric Taylor (Kyle Chandler) and “his boys,” the Dillon Panthers.

We meet star quarterback, Jason Street and his girlfriend, Lyla Garrity in the very first episode, which also saw Street paralyzed on the field. It's shocking to realize that in real life, Garrity was also dating the star player; then actress Minka Kelly was dating Yankee Captain Derek Jeter while still playing Garrity.

Don't panic people - the incomparable Jeter was not breaking any laws, he was only six years older than the model-actress. Kelly, however, was a good few years older than her character and in a twist and exception to the ten-year rule, Garrity was a student at Vanderbilt University - making Minka only a few years older, but still too old to be a student in college.

Leonardo DiCaprio – Catch Me If You Can

With a (no pun intended), catchy theme song, the artistry of Steven Spielberg, a story that traversed the colorful sixties and seventies, not to mention not one, but two of the most likable and bankable stars on the planet squaring off against each other – Catch Me If You Can is one of the classics of the new millennium.

Telling the crazy-but-true story of Frank Abagnale, who at 19 years old, became a master fraud artist and con man, making his own checks and convincing people he was everything from a college professor to an airline pilot, fanciful stuff for the time and more likely than not, something that could almost never happen in today's day and age.

It seems that no matter the gender, ten years more or less older seems to be the mandate for a lot of roles in Hollywood (perhaps it has something to do with the camera adding ten pounds, maybe adding ten years does something too), here is no different. Just about every Gen-X girl’s biggest crush, Leonardo DiCaprio was already 27 years old when filming began.

Keiko Agena – Gilmore Girls

For seven years, we got to know the mother-daughter combo Lorelai and Rory Gilmore, and all of their wacky friends and neighbors who all lived in fictional Stars Hollow, Connecticut. Rory’s best friend was Lane Kim, one of the earliest examples of an Asian-American being depicted realistically on TV. She constantly rebelled against her parents’ strict upbringing. She and Rory had even hollowed out some books to store forbidden CDs.

Fun fact - both the actress that played Lane, Keiko Agena, and Lorelai, Lauren Graham, were born in Honolulu, Hawaii. They're also only six years apart in age. Keiko is closer in age to the mom of The Gilmore Girls than she is her TV-bestie, Rory Gilmore (Alexis Bledel). Agena played Rory’s best friend and confidant, Lane Kim for the entire series run.

With a twelve year difference in age between herself and her character, Agena can thank her youthful porcelain skin as one of the reasons she was able to pull off the role. Often, actors look way too old for their part, but here if you didn't know Keiko was nine years older than Alexis Bledel in real life, you would have never guessed.

Stockard Channing/Vanessa Hudgens – Grease

Generally, the median age between a character’s age and the actor or actress who plays them is about 10-12 years older. This holds true especially when the characters are in high school. There are exceptions to the rule, of course, both older and younger. At 33 years old, Stockard Channing was definitely one of the exceptions when she played Betty Rizzo in the beloved Grease.

To be fair, pretty much the entire cast of the original film adaptation were all a little too old to be in high school at the time, but it was pretty funny to see a woman who could have had a high school-aged kid herself at the time playing a high schooler. Ever since the role of Betty has more or less always been played by a much older actress at the time. Channing's not the only one.

Besides Channing, comedian Rosie O’Donnell, along with, most recently, Vanessa Hudgens have taken on the role for last year’s big made-for-television production, making Betty Rizzo the most consistently older teenager ever.

Justin Long/Maria Thayer – Accepted

In the grand tradition of slacker college comedies like PCU and Animal House comes Accepted. The movie answered the age-old question of what do you do when not one single college accepts you?

You just make up your own of course. Justin Long stars as perennial slacker and prankster, Bartleby Gaines, who after being rejected from every college in the land, somehow gets the idea to tell his folks he has been accepted to the completely made up South Harmon Institute of Technology (spell out the initials, folks).

Long fits the ten-year rule perfectly - he's 28 playing an 18-year-old. He's not alone here either. Fellow reject, Rory Thayer helps to make South Harmon an actual college, and she's played by 29-year-old Maria Thayer. They're joined by both Jonah Hill and Blake Lively, who were both college-age when the flick came out.

Michael J. Fox – Back To The Future & Family Ties

With a squeaky, nasally voice to match his squeaky-clean image, Michael J. Fox was America’s favorite teenager for nearly a decade on Family Ties. As Alex P. Keaton, his rebellious teenage phase against his hippie parents was to be a young Reaganite Republican. For those that don't know, the series was one of the quintessential sitcoms of the decade and a springboard for Fox to go on to superstardom.

Concurrently, as Fox helped elevated Ties to iconic status, he was forging an even more memorable path, playing Marty McFly in the Back To The Future trilogy. At this point, if you haven't heard of BTTF or don't find it a fun way to spend a few hours, you either don't have ears or just don't like movies.

In either event, both Alex and Marty were way younger than the teen idol that played them. Alex was 17 when Family Ties started, putting Fox four years older. Place your bets on how old Marty McFly was at the start of BTTF, based on Fox being born in 1961 and the film coming out in 1985? You guessed it - ten years younger than Michael J. Fox was IRL: 14. America's favorite teenager wasn't even a teenager when he took the world by storm.

Olivia Wilde – The Wolf Of Wall Street

Hollywood is a funny place. Besides its casting decisions, there are a plethora of films that highlight and celebrate the lives of rogues and scoundrels, allowing viewers to not only get caught up in their schemes and devious tactics but become romanticized by them as well. One of the better films paying homage to a modern-day rogue is The Wolf Of Wall Street.

In the Scorsese-helmed biopic, a 39-year-old Leonardo DiCaprio plays 27-year-old stockbroker, Jordan Belfort, chronicling his rise and fall from swindling people. DiCaprio, of course, shines in the role and just like most of his other films is wildly likable, regardless of the fact he's playing a guy who conned a lot of people out of a lot of money.

Never mind that Leo was again playing younger, but strangely enough, his possible co-star, Olivia Wilde, was deemed too old to play his wife - and she's ten years younger than the actor was! Margot Robbie, much like Goldilocks, was deemed “just right” for the role at 16 years younger than Leo at the time.

Drew Barrymore/Neve Campbell – Scream

Considering how often horror movies are released these days and how well they do in theaters too, it's amazing to think how the genre was in the gutter in the mid-nineties. With mostly direct-to-video terrible flicks with bad effects and laughable prosthetics, the big icons of the eighties had become parodies of themselves, Chucky had become adorable, Freddy had even gone meta with A New Nightmare.

For horror fans, it was enough to make a fan…Scream, which is exactly the kind of movie that the genre needed. In not taking itself too seriously, being too meta, but still providing scares, Scream took theaters by storm and spawned a new franchise that continues to this day, as a TV show on MTV.

It all started with a dreaded phone call to young Casey Becker (Drew Barrymore) by the killer who would come to be known as Ghostface. The shock that such a big star like Drew wouldn’t be making it past this intro meant anyone could be a target. Even the other topic of this entry, series star Neve Campbell as the apple of the killer’s eye, Sidney Prescott. Both lovely ladies were 21 and 23 respectively; which thankfully breaks the ten-years-older casting, but still places both hotties well above high school age range.

Sarah Michelle Gellar – Buffy

If there was ever a modern version of King Solomon in Hollywood, seemingly Joss Whedon would be it. Sure, some of his own creations (Firefly, Dollhouse) didn’t last too long, but both shows, along with the rest of his shows, still have strong fandoms. If the guy’s name is on the project, chances are it is a memorable one.

Of course, his most memorable, beloved, and cherished creation is Buffy, The Vampire Slayer. For many fans, their love of Buffy stops and starts with the seven-season run on the WB and UPN networks. Starring a then 20-year-old Sarah Michelle Gellar as the titular role, the series focused on the trials and tribulations of getting through high school, while fighting blood-sucking vampires and other demons, ghosts, and androids…even if Gellar and other stars were several years removed from high school at the time.

Troian Bellisario - Pretty Little Liars

Since the cable network, ABC Family / Freeform’s inception, the network executives have done a great job of combining older stars who were famous in their youth with up and comers to create new soap operas for the whole family to get behind. Pretty Little Liars was no different. Using actors like Chad Lowe (Life Goes On) and Holly Marie Combs (Charmed) might have been a good way to reel in some older fans in the beginning, but the wildly zany stories and lies spun by the Liars kept them coming back for more.

One of the Liars was Spencer Hastings, played by Troian Bellisario; who also played Spencer’s twin, Alex Drake. As the preppy girl of the group, Spencer and her friends try to find out who the mysterious “A” is and why she/he is targeting them.

All four of the main protagonists of the series are all played by actresses older than their roles, Troian is not only the oldest in the cast at 25 when the series started in 2010 but she was also nine years older than her character and a good 4-5 years older than her co-stars. After elementary school, Bellisario would have never again been in the same building as her other Liars co-stars. She's also robbing the cradle with all of her TV boyfriends.

Emily Kinney - The Walking Dead

For the past eight years, The Walking Dead has drawn huge audiences, ratings, money, and most importantly, a tremendous fan base. Part of that love is thanks in part to the characters and their interactions, which is what makes fan appreciation for Beth Greene even more important when you consider how minor of a character she was and the season she debuted in.

Debuting on the show as part of the second season, Greene was one of Hershel’s daughters (along with Maggie) that kept their zombified family living underneath the family farm. It would take the entire family the whole season to figure out that their loved ones were gone; after her initial depression, Beth became a source of inspiration and hope for the group.

While Beth was a high school student, Emily Kinney was 26 years old when she was cast in the role in 2011. Strangely enough, there was no reason to make her a high school student at all. Not one single storyline she was in revolved around her being a teenager, and just made her brief friendships with both Carl and Darryl creepy for different reasons.

Jennifer Grey – Dirty Dancing

“Nobody puts Baby in a corner” is probably one of the most quotable lines in movie history. Taken from Dirty Dancing, the line refers to the main character, Frances “Baby” Housemen, played by Jennifer Grey in a star-making role. Star-making and jealousy-inducing, as just about every girl in the world wanted to be Baby and have the time of their lives, burning up the dance floor with Johnny Castle (Patrick Swayze).

The seemingly throwaway line has become a calling card of the film, harkening back to the film’s climactic dance scene, and now a Fall Out Boy song.

While Grey didn't have too many high-profile parts after this one, it's still impressive to have such a memorable role in one of Hollywood’s all-time classics. Grey makes our iconic list too - she was 27 when the film hit; which is the magical ten-year gap between the role and the actress.

Tobey Maguire – Spiderman

Comic book fans were sent into an absolute tizzy when it was announced that their friendly neighborhood Spiderman was finally coming to the big screen. Directed by acclaimed director, Sam Raimi the project was on target to become one of the biggest hits ever at the time.

Raimi cast then relatively unknown indie actor Tobey Maguire to play Peter Parker as they told the story of how a high school nerd got bit by a radioactive spider and became a superhero in the process. The only issue (at least until cameras started rolling), was that Maguire would be 27, 29, and 32 by the time each film in the original trilogy came out. Now while Peter would be one of the few comic book characters to age and come of age, that age difference and gap had him maturing too fast!

Unlike most of the actors on this list, Maguire didn't look 17 at all. True, he didn't look like he was 27 either, but his “youthful looks,” weren't and aren't that youthful; which didn't help the guy pull off a high school student at all. The look for worse for him when he went through his godawful emo-phase in Spiderman 3.

Kristen Bell – Veronica Mars

While she didn't catch on as wildly as Buffy Summers did, teen detective Veronica Mars and her show, Veronica Mars did catch on and garner a devoted fan base of rabid fans who did adore the series. So much so that fans supported a Kickstarter campaign for series creator Rob Thomas to film a concluding movie.

Even though the concluding movie is set nine years after the show ended, Kristen Bell is still too old to be playing a high school student, which Veronica Mars was when the series began, she was 17 and Bell was 24 in 2004 when the series began.

Especially nowadays, Hollywood needs a new rule - if you're too old to be in high school you're too old to play high school. The industry already has a hard enough time keeping itself in reality. Sure Kristen Bell looks way younger than she is now, even pushing closer to 40, but you can’t push yourself to be a better actress if you're always playing a kid.

Alan Ruck – Ferris Bueller’s Day Off

If you have a pulse and a pair of eyes, then you've seen Ferris Bueller’s Day Off. You certainly had an inkling at one point or another to even try and be just like Ferris Bueller, who didn't seem to give AF about anything other than cutting school and having a grand adventure all over Chicago.

He was a teenage rebel who outsmarted everyone and had the ultimate day off, even getting to march in a parade. But the real star of the movie, more realistic star anyway, was Ferris’ best friend, Cameron Frye.

Played by Alan Ruck, the guy was 13 years removed from high school when he played the hapless teenager Cameron. Here, being 29 years old at the time actually helped Ruck in his portrayal. Ruck being out of touch with what teenagers were into at the time worked well for Cameron, who certainly wasn't part of any hip crowd at all.