Competence Zone

''Every television show has its own average age-range of competence. Only people inside that range, whatever it is, are likely to be competent at anything relevant to the show.''

This holds whether you're trying to save the world or just performing A Simple Plan. If you're too young or too old, you're outside the Competence Zone of your profession, which makes you dead weight. The 'kid' is innocent or bratty, and needs protecting. The old guy is cranky and complains too much.

That sounds like common sense, but television often takes it a step further: the Competence Zone becomes a relative thing. A 17-year-old among twenty-somethings is just as much the "kid" as the ten-year-old among thirty-somethings; a 22-year-old is an "old guy" on a show about tweens just as much as the 55-year-old father is on a show about young adults. The only difference between shows is that the zone itself gets wider or narrower.

This occurs because the main cast of a series are often near the same age, as is the target demographic. We relate to them, so we can subjectively ignore ages even much higher than intelligence may indicate. However, any deviations from this become obvious, and seem to demand explanation.

If the older/younger characters are just as competent, there's usually some inherent quirky trait allowing them to be so. A Creepy Child, an Adult Child, a pseudo-child and Wise Beyond Their Years are ways to play with personalities to make them fit into the Competence Zone where the writers want them to, while mascots and Team Pets have a vague enough age that you can fit them anywhere you want. Occasionally, someone is far enough out of the Competence Zone that they become useful again -- grandfatherly mentors are more useful than parents, and genius pre-teens are more useful than the average high school student. This may be because authority conflicts or their notable absence are less likely to distract from the story this way. A pre-teen genius would be less likely to conflict with adult characters and demand more autonomy than a 17-year-old, whereas a grandfather would be less likely to attempt to exert control over a teen cast because it's not his job to be the strict authority figure.

Most inexplicably, if the main cast ages during the run of the show, the Competence Zone may move with them. On the other hand, if the show changes to focus on different characters as old ones move on, the original cast may slip outside the Competence Zone.

Subtropes include Adults Are Useless and Teens Are Monsters. See also Improbable Age, where the Competence Zone is imbalanced enough for viewers to notice. In a Teenage Wasteland, whether the characters have reached the Competence Zone yet or not with respect to self-governance varies.

= Examples of too young: =

Anime and Manga

 * In Love Hina, Motoko is a serious Huge Schoolgirl who's treated like the other twentysomethingers, while the meek Shinobu is treated like a kid, despite them being only three years apart in age.
 * Likewise Sarah's first appearances simply establish her as a Bratty Half Pint. Both the comic and show have a deliberate and funny 'reveal' scene where we notice than even the small Shinobu is much taller than her.
 * Nah, Motoko is generally portrayed as being in the middle of the hierarchy, after accounting for the fact that she could kick the ass of almost every other regular cast member's ass, put together. Outside of fights, the regulars who were older than her keep calling her with the "chan" suffix and she follows all their leads without question (except, obviously, Keitarou's) and holds a similar position above those younger than her except Suu (who is, canonically, her best friend). Or Sara. Or Kanako. Okay, so Shinobu and Nyamo are the only people younger than Motoko that listens to her... or anyone else, for that matter, but she still seems to have more influence with the older cast.
 * Future Boy Conan sets this line at around 10. The heroic kids are not only smarter than most of their adult counterparts, the title character is stronger and faster too. Once you become a grandparent you are competent again. At least until you get killed.
 * This seems to be in effect for Hayate the Combat Butler, everyone is within three years of 16 who is competent. The others are side characters just tossed in for humor (which of course is the point of the story).
 * Nagi's grandfather Mikado is old enough to be part of the circle-around mentality, except he's the one recurring character we can be sure is a villan. Isumi's great-grandmother also circles around, but is on the protagonist's side after her entrance (when she plays at being within the competency zone).
 * Athena plays with this one, supposedly being the same age as the male lead for her first two appearances, while Older Than They Look questions are tossed about. . So it's unknown if she's competent, circles around, or stands firmly outside.
 * In The Law of Ueki, all the fighters are middle school students.
 * In Full Metal Panic, all the people who do any work or accomplish anything (especially with regards to saving the day) are 16 years old. Sort of explained as most of the 16-year-olds are actually Whispereds - special geniuses born with knowledge of Black Technology, all of whom were born at almost the exact same time. Except... the explanation still doesn't cover why Sousuke, who is also 16 (and who is the most useful character (he is the main character after all)),is still a young genius despite not being a Whispered. The rest of the characters (who are older) don't do nearly as much for the plot.
 * However, Sousuke has more experience than some older characters. He has been a soldier since he was a child, while Mao and Kurz weren't. He is younger, not more inexperienced.

Comic Books

 * In Runaways, all the heroes are teenage runaways except Molly, who is an 11-year-old. Even though Molly has superstrength and routinely pounds bad guys with it, the other kids keep sheltering her. When they fight off a supervillain when she's out, they decide to never tell her that a villain ever attacked. However, adults explicitly note more than once that she acts childlike to lower people's defenses, and she's showed plenty of competence in her Day in The Limelight story.

Literature

 * In the Xanth book series by Piers Anthony, the Adult Conspiracy is a seemingly magically-enforced pact among every adult in the world to prevent children from learning about sex, swearing, or nudity. Every adult human, at any rate - the rest of 'em don't seem to care too much; centaurs and demons being depicted as more carefree, for example.
 * In the earlier Harry Potter books, Ginny was outside the Competence Zone and in general portrayed as a helpless innocent. This is despite the fact that she is only one year younger than the trio and thus always the same age Harry was in the last book. This was subverted in Harry Potter and The Order of The Phoenix when Ginny is allowed to help after pointing out she is four years older than Harry was during his first confrontation with Voldemort, giving her the opportunity to show that she Took a Level In Badass.
 * Followed confusingly in the climactic battle, where the good guys weaken their numbers by sending the under-17s away. This is justified because, well, adults don't generally like youths putting their lives on the line, and Harry and Co.'s adventures were generally without adult approval.
 * Sending away the under-17s could also be seen as a parental consent thing. You think Hogwarts would stay open if parents thought the teachers were willing to draft the students to fight their battles? Look at what the Ministry did when they were accusing Dumbly of using Hogwarts to train his own personal army to topple Fudge and take the title of Minister by force.
 * In the first book, Ginny wasn't at Hogwarts, and in the second and third she had a crush on Harry that made her too shy to participate in their adventures much. Book four focussed mostly around Harry, so book five is arguably the first time she could help the main trio.
 * The Babysitters Club takes this trope Up to Eleven. Mallory and Jessi are mature enough to babysit and be trusted to wander around Stoneybrook alone among other things. Most ten year olds are not. It becomes a major plot point a couple of times.
 * In The Egypt Game, eleven-year-olds April and Melanie worry about nine-year-old Elizabeth being outside the Competence Zone. She turns out to be more competent than they expect, although she's still portrayed as a Naive Newcomer. Oddly, they had no such reservations about Melanie's four-year-old brother Marshall.

Live Action TV

 * Angela from Degrassi the Next Generation is a little girl of highly Vague Age, surrounded by teenagers. Her sole purpose on the show is to be a pure innocent who cannot be exposed to the typical Soap Opera nightmares happening around her; the other characters know they've gone too far when something they do affects Angela.
 * 15-year-old Angela's 10-year-old sister Danielle in My So Called Life is too young to be part of Angela's group, but does have sarcasm down...
 * The 13-year-olds of Ghostwriter were competent, but anybody younger become a comic-relief sidekick. Particularly strange was when Gabby got too old to be comic relief, became competent, then was replaced with a younger actress who acted even more naive than the original Gabby did.
 * They did subvert this once: When Jamal's family takes Casey in, they try to keep the truth from Casey about her alcoholic mother, and this is more trouble than just telling her would have been.
 * Stargate SG-1 treated Jack O'Neill's teenage clone as just a kid and sent him to high school, even though mentally he was no younger than the original.
 * Then again, mini-Jack doesn't seem too upset about being surrounded by teenage hotties who are clearly no match for his superior maturity and experience.
 * Alternately, he may have no intention of staying in high school. Jack probably knows how to disappear, and who would think a fifteen-year-old actually had the memories of a fifty year old special ops officer?
 * On Buffy the Vampire Slayer, Dawn is a clueless freshman when first introduced, despite being at most one year younger than Buffy was when she started killing vampires every night. Lampshaded on multiple occasions when Buffy is being protective (over- or not).
 * Abused by Seasons 7 and 8 when it comes to Dawn. In Season 7 she quickly goes into the role of The Smart Guy and is generally much more useful. Then Buffy tries to have her taken out of the battle by having Xander chloroform and kidnap her. She tazers him and drives the car home after waking up. Season 8 has her saving Xander's life and then later on being the only one to realize that Buffy might not be as good as they think it is.
 * Subverted in Drake and Josh, in which the main characters' younger sister Megan is portrayed as being more competent than most of the adults around her.

Video Games

 * Metal Gear Solid is notable in that it has a much older cast than usual in video games or media in general - much of the cast is in its thirties or forties or beyond. The result is that the Bishonen, in his mid-twenties, falls outside the Competence Zone and becomes This Loser Is You.
 * The two youngest kids of Backyard Sports, Luanne Lui and Ronny Dobbs, were removed from the series after Backyard Baseball 2007.
 * Played straight, almost to an extreme in Final Fantasy IX in regards to the six-year-old Cheerful Child and summoner Eiko. She is equally as capable as her older comerades in surviving and tackling dangerous situations head on, and garners her Precocious Crush on the sixteen-year-old Zidane with poetry, cooking, and quoting classic literature. To top it off, when two members of the group go into a Heroic BSOD, Zidane puts Eiko in charge. If Eiko was the same age as Garnet, Zidane's actual Love Interest, it would be highly likely that some serious shipping would ensue.

Webcomics

 * In the Web Comic Questionable Content, most of the cast is in their early-to-mid-20s, but Ellen first appears just before her 18th birthday. Sometimes she's as competent as the rest of the cast, but she has her moments, like not knowing (in a discussion of porn) that it's considered unusual for a girl to do double-penetration with her boyfriend and some other dude.
 * Addressed in Gold Coin Comics when asked about their age.

Western Animation

 * Jade from Jackie Chan Adventures is considered too young to fight against forces of evil, or anything for that matter, not that this actually stops her of course.
 * In Recess, the Kindergarteners are portrayed as wild savages, and the adults are generally clueless. Older children like the King and his guards are often so concerned with their own power that they're incompetent rulers.

Real Life

 * In any company which requires selling something, particularly a form of credit or anything else a bit financially risky or important, a customer is far more likely to trust and therefore sign up with an older person, even if a much younger person uses exactly the same selling-pitch.

= Examples of too old: =

Advertising

 * If most cereal commercials (namely Apple Jacks and Cinnamon Toast Crunch) are to be believed, adults are the biggest morons on the planet and don't understand anything and just exist to be scorned mercilessly for their idiocy by their children. They are also physically incapable of grasping why children enjoy cereal.
 * Fuck off, dad.

Anime and Manga

 * Cheerfully blown to pieces by Magical Girl Lyrical Nanoha. Where most magical girls lose their powers as they grow up, Nanoha's ability to blow shit up only gets bigger and flashier as she goes from a pre-teen in the first and second series to an adult in the third and a mother in the fourth and fifth.
 * Not totally averted, tough. It's implied that Nanoha effectively lost part of her power as a consequence of constantly pushing herself beyond her limits as also her age, in FORCE she uses a lot of support equip to be able to keep up fighting. Also played straight on the same season with the Wolkenritter, their fightsyle, weapons and powers are simply too outdated to keep up with modern threats and are easily defeated as a consequence.
 * In Ranma 1/2, nobody between the age of 19 and 100-300 is worth crap -- except Dr. Tofu, who vanished without a trace early on. Ranma's father, though one of the most powerful martial artists in the series, is a coward, a leech, a bully, a criminal, and much more. Akane's father is better, but he's still a an emotional wreck who lets people use him. Principal Kuno is... one of a kind. None of them ever accomplish anything on their own; the teens have to do it. (The senior citizens, Cologne and Happosai, are just as messed up, but they're actually competent.)
 * Let's be fair. Ranma and friends are pretty messed up too.
 * Let's not forget Hinako Ninomiya -- biologically in her late 20s, even if she's only that way outwardly (and mentally) half the time. She'd actually be pretty deadly if that were her aim, but all she really wants is to teach... which is a job she performs marginally better than Principal Kuno does his.
 * In Naruto the zone is similar. If you're a twenty-sixty something adult ninja, even if you have years of experience, you're nothing but a mook. Even if you are competent, it'll just be used to Hype up the bad guy so the kids look better when they win.
 * Although the few characters who are genuinely getting on in their years (Onoki, Hiruzen, Madara and arguably the sannin) tend to be just as,if not more competent than the main characters.
 * The tween heroes from Digimon Adventure are apparently too old to save the world in Digimon Adventure 02 -- even though only three years have passed. Sure, they show up as cameo characters, passing on knowledge or goggles to the new heroes, but with the exception of the two youngest, they make a big point of not participating in the struggle. The big justification here has more to do with the fact that they're simply too busy to do so now that life is catching up to them; hell, Mimi doesn't even live in Japan anymore.
 * It is soon explained in the series itself that it's more the fault of their partner Digimon than the kids': they can't evolve at all with the Digimon Kaiser's Dark Towers around, so they are worth shit in a fight... hence the new recruits.
 * Or the writers' fault for enforcing the trope. Deus Ex Machina gives all the new Transformation Trinkets to the young ones, even when this results in some of them having two.
 * They do eventually get rid of the black towers, but the original characters are still limited to cameos.
 * Except
 * As soon as the Dark Towers were destroyed, there was a flashback explaining about how the Adventure characters gave up their ability to evolve to the Perfect level sometime during the Time Skip, so even if there were no Dark Towers, as soon as Ken figured out how to control Perfect-level Mons, they would have been toast anyway. The fact that this wasn't mentioned until the series was half-over makes it come off as an easy, spur-of-the-moment contrivance to justify focusing on Daisuke and the others at the expense of the older kids.
 * Which in itself would be a fairly standard Restart At Level One to let the new characters be useful. But they are too old to even try to get their powers back.
 * The cameos, while brief, make up for it in spades. Remember WarGreymon's re-appearance?
 * Arguably all the Digimon series is this trope. Except perhaps Digimon Savers.
 * And Devil Hunter Yohko is the same -- Yohko and her grandmother are both Devil Hunters, but Yohko's mother is a boozy slut who didn't want to take on the family duty to fight supernatural monsters and disqualified herself as quickly as she could.
 * With the exceptions of Run-Run and Sly, anyone significantly older than Kukuri and Nike in Mahoujin Guru Guru is downright useless. The Old Kita Kita Man is practically a millstone as often as he's useful.
 * Neon Genesis Evangelion is a rare case where nobody is in the Competence Zone. The older generation has both brought ruin upon the world, and left the younger generation too emotionally crippled to fix it.
 * Well, Ritsuko is extremely competent in her area. Same for Misato, who's scarily focused and competent when she's not goofing around. And the Eva-pilots fare pretty well for emotionally disturbed teens in charge of kicking some giant monster butt with a giant
 * Perhaps this belongs as a deconstruction of the Competence Zone in Humongous Mecha. Every competent character is a pretty damaged individual, for every competent act onscreen the same character screws up in another aspect of life, and in the end competence counts for nothing.
 * Depends on what you mean by "competent". Technically, everyone followed through with EXACTLY what they were supposed to do. Said final goal, of course, is not exactly....something most people would want, but they indeed succeed in achieving it.
 * It's not just about emotional states: only people born after the second coming can synch with the Evas, so anyone past their teens just can't pilot them.
 * Strike Witches' competence zone is basically ages 12-18 - its a major plot point that the oldest member of the team is losing her powers.
 * In Soul Eater prior to taking their various levels in Badass the kids were clearly outclassed by their teachers. Now, groups of students form an 'elite' unit who apparently outperform the average adult Shibusen uniformed mooks, and the adults previously shown as competent have recently been worfed in the space of a page or two.
 * Subverted in Tiger and Bunny, where middle-aged Kotetsu T. Kaburagi manages to be deceptively competent and extremely heroic despite his frequently lampshaded "past his prime" status. Word of God says that the character was basically created to give the typical anime competence zone the middle finger.

Comic Books

 * Comic-book example: Ultimate Spider-Man is very deliberately based on this. The main theme of the story is that adults have all screwed up the world, and the teen-age Spider-Man, who barely understands what they've done, has to do his best to fix it. At one point, Spider-Man directly tells the reader this in a monologue.
 * Similarly, in Runaways, when he feeds the "With great power" line to the titular characters, Gert scornfully remarks, "That's inane. Most people in life never have great power, and the few that do are almost never responsible with it. The people with the greatest responsibility are the kids with no power because we're the ones who have to keep everybody else in check", to which he replies (totally deadpan), "Wow. You are totally gonna be an Avenger when you grow up."
 * Happens in the Legion of Super-Heroes to various degrees, in the first years of the original, in the reboot, and in the threeboot, with teenagers being the only superheroes in the setting and R. J. Brande as the useful old mentor. Especially so in the threeboot, with the Legionnaires being on the forefront of youth rebellion throughout the galaxy and where Supergirl in the Legion was noticeably more mature than she was in her own book because she's not in the Competence Zone there. (In the current version the Legion has aged enough that the Competence Zone is just "adult" and not noticeable.)

Fan Fic

 * The Klein family, from Script Fic Calvin and Hobbes: The Series, are an aversion; they and Calvin get along quite well.

Film

 * Super 8 seems to suffer from this, with many of the children having adult competence levels and developed skills, and most of the adults (except Jack) just following direction. And the young adults are potheads.

Literature
""The Patrol's found out that after your fifteenth year you somehow 'put away these things.' The glory dies away, as new yearnings come, until you find yourself a stranger to what you used to be. So the Patrol makes you step down before you reach that point, Tommy.""
 * A Series of Unfortunate Events, in which every single adult (with the exception of Count Olaf and the Snicket siblings) is much, much less competent than infant Sunny.
 * Even Count Olaf isn't exactly competent by himself, it's just that he has a lot of resources to work with and usually only has to fool incompetent people. This becomes most apparent in the final book where his usual Paper Thin Disguise doesn't fool anyone.
 * In the Great Brain books, boys start leaving the Competence Zone around age 13, when they start working and develop an interest in girls and therefore have less time for kids' games.
 * The short story "Age of Retirement" by Hal Lynch (published 1954), had the Space Patrol mandatory retirement age as sixteen. (What saved it from being a horror story about Child Soldiers was that the weapons used by cops and "afflicteds" alike were all nonlethal.)


 * Apparently, except for Mazer Rackham himself, nobody over 12 is competent to command in the Ender's Game universe.
 * Of course, the books justify this by insisting that these kids are the first generation to be put through Battle School, where they are raised to think tactically -all the time-.
 * Also this doesn't make older people incompetent - they're just using the children's special abilities in an all-out war. There are many types of leadership and competence.

Live Action TV

 * In Degrassi the Next Generation, no teens more than a year older or younger than the main cast even exist. Every adult on the show who wasn't a kid in previous ''Degrassi" series is either a Spear Carrier, incompetent, evil or all three. Those who were there before are in the zone despite what the current generation think. ("My mom's cool but she's not that cool.") All university students (except the main cast, once they go to university) are competent and evil.
 * Despite some episodes of Buffy the Vampire Slayer where Giles is referred to as the useless old English fuddy-duddy like when he tells Buffy she will die in the season 1 finale, he uses his magical know-how to save Buffy's life in episode two, so even though he's probably older than her mother he doesn't fit this trope. Joyce Summers, however, fits it perfectly because Buffy keeps her from knowing about the slaying, as does Principal Flutie.
 * Wesley is a subversion as a young(er) person who's painfully outside any zone of competence (at first).
 * Really, he was outside both competence zones. He was outside the 30+ one (Giles, Angel, Jenny when she was alive and all of the Big Bads) but outside the under 20 one. The under 20 one moved upwards over time while the other one stood still.

Tabletop Games

 * Bliss Stage: Soon after their 18th birthday, all of the teenage heroes Bliss Out.

Video Games
"RPG characters are young. Very young. The average age seems to be 15, unless the character is a decorated and battle-hardened soldier, in which case he might even be as old as 18. Such teenagers often have skills with multiple weapons and magic, years of experience, and never ever worry about their parents telling them to come home from adventuring before bedtime. By contrast, characters more than twenty-two years old will cheerfully refer to themselves as washed-up old fogies and be eager to make room for the younger generation."
 * Extremely common in many videogames, most especially console RPGs, from the Grand List of Console RPG Cliches:


 * Averted in Tales of the Abyss: The most powerful character in the game (story-wise) is Jade Curtiss aged 35. He tends to make comments about old folks like him not being as competent as the younger members of the group all of which are below age 20.
 * Jade is one of the most powerful and brilliant fighters and mages (and the greatest scientific genius) in the world at the start of the game. By the time you level him up to the point where he's as strong as he was before he got sealed, you get a skit where he admits that the rest of the party has managed to catch up to his level in the time it took him to undo his fon slot seal. Not to mention that, plot-wise, Luke, Ion,  all have much more powerful magical capabilities than him, and Van is a much better fighter. Jade's scientific genius is only even remotely approached by Dist, though, and they're of an age with one another.
 * Well, Guy is actually 21, and he's treated as a more competant swordsman as Luke (at least early on) and is easily one of the most emotionally mature people in the game.
 * Yet another game in the series, Tales of Vesperia plays it straight with Raven, 35 years old, being called "old man" and constantly whining about his age.
 * Handled with unusual specificity in Final Fantasy VIII, where nearly all the principal characters are 17, except for Quistis, their instructor, who is 18.
 * Although, Laguna and his friends Kiros and Ward are in their 20s-30s and are shown to be very competent soldiers. Yes, even Laguna.
 * Mostly followed in the Golden Sun series (most party members are in the 15-18 age range, except for Kraden, who doesn't take part in battles), but averted in a few cases; Piers in The Lost Age is hinted to be considerably older than he looks but refuses to give a straight answer about his age, and Eoleo in Dark Dawn is in his thirties.
 * Surprisingly averted in Infinite Space, considering how heavily anime-influenced this game is. Many of the "old" characters (including your crew members) are just as competent as the "young" ones, if not more.
 * Justified in TCTRPG as all the adults are being puppeted by the Others. Only children can actually think independently.
 * .hack averts the trope. Yes, a lot of the main characters are teens. However, in the first four games, we also have three adults (Helba, Lios, and ), and one pre-teen kid (Wiseman), all of whom are thoroughly competent, and play major roles in the story.

Webcomics

 * Ozy and Millie plays with this by featuring several very childish adults, in contrast to the very grown-up children it stars. However, that only makes up about half the cast. One of the main themes of the strip, as stated many times by its creator, is that maturity often has little to do with age.
 * A subversion of this serves as a primary plot point in Golden Age of Adventurers. The four older adventurers really are past retirement age (and therefore supposedly not capable of really looking out for themselves, let alone going on adventures). However, for the most part they are very skilled at what they do and can get along just fine.
 * Averted in Homestuck, in which the main characters' mentors are increasingly revealed to be very capable and it's implied they had their own plan to stop Jack going on in the background. It takes Jack becoming a Physical God to overwhelm and kill them, but in fairness, he's perfectly capable of killing the heroes too (and has already).

Western Animation
"Jake: "Finn can handle it: he's twelve.""
 * One of the main thrusts of South Park is how the 3rd/4th grade main characters are more competent than adults because they have yet to be indoctrinated into various foolish aspects of adult American culture. Kids who are a few years older than the main cast are shown to be dominated by their adolescent hormones, while younger children are little more than babies.
 * The Life and Times of Juniper Lee has a mystical gift jump a generation. June and her brother are competent, her grandmother is competent, but her parents are clueless.
 * Which is almost identical to the setup in Jake Long: American Dragon, only swap the genders (Jake and his little sister, and his grandfather are dragons) and make one of the parents clueless (Jake's mother is aware of their family heritage)
 * The father gets clued in eventually as well. Or least learns about the whole dragon thing...
 * This actually makes the Jake Long example a bit of a subversion: once his dad finds out about everything, he becomes pretty competent, singlehandedly wiping out an army of shadow demons that even the whole dragon council was having trouble with.
 * Ditto with Hay Lin's family on WITCH -- her grandmother is a Guardian, she's a Guardian, her parents are just clueless. The other parents on the show are decent but stupid.
 * Not stupid, per se, they're just fairly good parents that don't know their daughters are saving the world when they break curfew thanks to the Masquerade. If they were stupid, it would actually make things easier on the girls.
 * Codename Kids Next Door takes the Competence Zone to extremes: anyone 13 or older is a threat to the Kids Next Door, and must have their memories of the organization erased. In this universe, unlike the real one, teenagers serve as loyal minions for adults. The show eventually subverted this in the episode "OP MAURICE."
 * Occasionally subverted.
 * Alternately, one could say being a KND operative, current or former, is the competence zone.
 * Avatar: The Last Airbender: another great kids' show featuring use of child soldiers in a genocidal global conflict. The main cast of teenagers range in (biological) age from 12 (Aang, Toph) to 16 (Zuko, maybe Jet?). Owing to many members of the intervening generation not being around, competence doesn't appear to pop back up until you start hitting the much older demographics.
 * Jet is about Zuko or Sokka's age, which isn't so bad until you realize he's been fighting the Fire Nation since he was much younger than the current cast of heroes, and has apparently gathered an entire following of children a la Peter Pan's Lost Boys. Smellerbee and Longshot are probably teenagers, but The Duke is 8. He seems to know a fair bit about explosives...
 * This is Justified in that the war has been going on for 100 years and most of the adults are either off at war, or back home trying to keep things together. or dead.
 * Well there are the elite top-members of the White Lotus Society, an entire group of BadassGrandpas who
 * It's inherent to the franchise, actually. The adults' short sighted pragmatism led to a hundred years of war, so it's up to a new generation of heroes to tackle the problem with naive optimism.
 * Mainly because the only one who can end the war is currently twelve and the only ones available to go with him are similar in age -- all the adults are fighting the war that's going on.
 * In Arthur, the adults are realistic enough, but fourth graders (a mere grade above Arthur and his friends) are portrayed as "tough big kids" who essentially act like teenagers and are often not too bright. This is heavily based on how Binky Barnes, who is their age, is portrayed in the books.
 * The Fairly Odd Parents tends to play this pretty straight, with Timmy's parents being stupid and impulsive. However, Timmy comes to lampshade this during the event where he chases Vicky through various TV shows, all which also include incompetent adults,
 * Largely averted in Kim Possible. Our heroes are teenagers, but their allies and enemies include tween geniuses, adults ranging from scientists and law enforcement to Mad Scientists and Kim's vast network of favours, and a ninja toddler.
 * Lampshaded in the Adventure Time episode "Tree Trunks":

Real Life

 * Any job description requiring sex appeal.