Not to be confused with the [[Film/TeenagersFromOuterSpace 1959 sci-fi movie of the same name]] (as seen on ''Series/MysteryScienceTheater3000''), ''Teenagers From Outer Space'' is a wacky, rules-light, {{anime}}-inspired RPG from R. Talsorian Games.

The concept of the game revolves around the aftermath of mankind's first contact with space aliens. In this case, since all the aliens come from {{One World Order}}s, they quickly become fascinated with Earth's cultural diversity. So much so, that sending your kids to high school on Earth becomes the next big thing. Naturally, with all those teenage aliens running around mingling with the locals and getting into {{Zany Scheme}}s, HilarityEnsues.

The game was based on comedy anime (particularly ''Manga/UruseiYatsura''), but was originally released in the '80s when anime was still mostly an underground sensation. So, it was written as a general comedic sci-fi RPG. After anime started becoming mainstream in the mid-90's, the game was reworked to make the anime influences the main selling point.

The game came in three editions: 1987, 1989, and 1997. The only difference is each successive version added another alien powers table, and different sample characters in each edition (with a lot of overlap)

The books also come with a list of adventure seeds called "Episodes", many of them based on the plots of episodes of real comedy anime.

!!This game provides examples of:

* AmusingInjuries
* {{Animesque}}
* BagOfHolding: The 4th dimensional purse, which holds six times its apparent capacity by using a miniature time machine to put your items into six different time zones.
** Also the Warpspace Overnight Bag (can hold dozens of outfits in a 1x1 tote bag, but only holds clothes) and the Black Hole Storage Closet upgrade for vehicles (can hold absolutely ''anything'', as long as you can fit it through the trunk door.)
* BlackWidow - According to the sample adventure, Nookians carbon-freeze their husbands after the wedding night.
* BreastPlate - The Battle Bikini item.
* [[CantHaveSexEver Can't Have Sex Ever]] - It's a rule. If two characters ''try'' to have sex, a hilarious interruption '''must''' ensue. [[WordOfGod The author]] explains this is due to [[RuleOfFunny Rule of Funny]].
* CaptainErsatz - Rami is ''totally'' [[Manga/UruseiYatsura Lum]] in a cat girl's body. Lum's body... that's the girl in the illustration on page 7.
** One of the girls on Page 4 looks a lot like [[WesternAnimation/SheRaPrincessOfPower She-Ra]].
* ClingyJealousGirl: Rami, and an inordinate number of plots provided by the game call for one.
* DistressedDamsel: A [[IncrediblyLamePun distressing]] amount of plots involve this.
* EarthIsTheCenterOfTheUniverse
* EasySexChange: The Boy/Girl Gun and Boy/Girl/Boy power
* EvilTwin: Episode 5 involves one of the player characters being visited by their tasteless, lecherous cousin who looks ''exactly like them''.
* ExactlyWhatItSaysOnTheTin - the game is about teenagers (or at least people who behave like stereotypical teenagers) from outer space.
* {{Flight}} - a possible superpower for aliens.
* FreakyFriday - The Personality Swappers.
* GenderBender: the Boy/Girl Gun and the ''Manga/RanmaOneHalf''-inspired power "Boy/Girl/Boy" in the 3rd edition.
* GodGuise and SufficientlyAdvancedAlien - subverted. The assorted aliens have strange and mysterious powers which generally put them into superhuman territory. Sure, the humans get stuff like "rich", "smart", typical high school social survival traits, but how do you hold out against an alien "jock" who can bench a tank? Oh wait... humans also get the Human Fake Out. Since the aliens consider Earth to be the Coolest Place in the Universe, most of them will believe practically ''anything'' a human says. Which makes encounters with the GreenSkinnedSpaceBabe [[HilarityEnsues very interesting]] when you explain that going to second base is a common human greeting among good friends on their own....
** This was a fan-made expansion that gave some more "bizarro" powers to humans, to all [=GMs=] to add elements of series like old Mecha animes, ''Manga/RanmaOneHalf'' and ''Anime/ProjectAKo'' to their campaigns. These included powers like Girl/Guy/Girl Trigger (contact with a specific stimulus caused the character to be affected as though hit by a Boy/Girl Gun, a {{Genderbender}} TransformationRay), Own a Big Mecha (the character has a piloted robot or super battlesuit made by one of their relatives- which meant they'd get ticked if it got damage) and a human version of the [[OneWingedAngel Monster Out]] power.
* GoneHorriblyRight - This will happen if you roll ''too'' high.
* HammerSpace / HyperspaceMallet - the Hyperdimensional Hammer, which can be purchased at your local store.
* HitPoints: Or more specifically Bonk points. Pretty standard, except a) you don't die if you run out, and b) you can lose them by being humiliated as well as getting hurt.
* HumansAreSpecial: Due to their cultural diversity, humans are considered the coolest beings in the universe, to the point that they can Fake Out aliens with claims like "plaid bellbottoms are cool" or "kissing is a perfectly acceptable way to say hello".
* InvoluntaryShapeshifting - the "Monster Out" ability.
* ImportedAlienPhlebotinum (Available ''cheap'' just about ''everywhere'')
* MegaNeko: Episode 8 involves a giant cat adopting one of the [=PCs=] as its own kitten.
* TheMenInBlack (The Alien Control Officers)
* NonCombatEXP: The game works on a voting method: the other players at a session make secret votes to decide if a player gets 1, 2 or 3 XP. The average is rewarded.
* NoSuchThingAsAlienPopCulture: Pop Culture is [[PlanetOfHats Humanity's Hat]], and the reason why so many Aliens are interested in the place.
* PunyEarthlings - aliens get all kinds of cool powers; humans can have more mundane 'powers' like connections to important people or loads and loads of money.
* TransformationRay: Aside from the Boy/Girl gun, there's also Featherface's chicken gun.
* RuleOfFunny - the game was designed to run on this.
* ShoutOut - Many to ''Manga/UruseiYatsura'', among others. The first two things on the alien powers list are flight and shooting lightning, even.
** "TFOS Does Winterfest" introduced an idea they called "Out of Control Power" where some external stimulus switches on one of the player's abilities, and one of the examples was [[Manga/RanmaOneHalf being hit with cold water]]. Maybe a coincidence, but considering whose work inspired this game in the first place...
* SlidingScaleOfAnthropomorphism - The various alien races are given a rough sorting based on how closely they resemble a human form (and how likely they are to send scientists scurrying to the nearest bomb shelter). Near Humans are perfect examples of HumanAliens and the GreenSkinnedSpaceBabe. Not Very Near Humans are defined by having a roughly humanoid form and nature: RubberForeheadAliens, {{Intelligent Gerbil}}s, PettingZooPeople, LittleGreenMen and TheGreys. Real Weirdies are anything else; StarfishAliens are most common examples, with InsectoidAliens also possible, but theoretically a Real Weirdy could also be an EldritchAbomination or even from a race of EnergyBeings.
* SpacePolice: [[Literature/{{Lensman}} The Benzmen ]]
* StockSuperpowers: Aliens can get all kinds of neat powers, including [[AnIcePerson freezing things]], [[PlayingWithFire breathing fire]], [[SuperStrength super strength]], [[SuperSpeed super speed]], [[TeleportersAndTransporters teleportation]], the ability to [[VoluntaryShapeshifting "monster out" and shapeshift]], creating [[BarrierWarrior shields]], [[ShockAndAwe zap people]], [[{{flight}} fly]], [[VampiricDraining drain "bonk" (hit points) from others]], and [[MindOverMatter telemove]] objects.
** SuperIntelligence: Probably the only [[StockSuperpowers Stock Superpower]] that PunyEarthlings are allowed to access because of its mundane and unimpressive nature when compared to the rest of the StockSuperpowers.
* WorldOfHam: downright encouraged in the game's rules. "Great Moments In Overacting" are specifically mentioned.
--> "Something underwater on an alien planet has just grabbed your foot. If you aren't screaming like a cat dipped in Nair, you aren't grasping the seriousness of the situation."