As a subtrope of {{Infodump}}, an easy way to present {{Exposition}} in a story is to have a character, often a lead character, as a lecturer or teacher in a classroom, conference or boardroom. Alternatively, particularly when the character is less experienced, they could be the one attending the lecture, class, conference or boardroom.

Compare ChekhovsClassroom. Both use TheLawOfConservationOfDetail in a way, but since {{Exposition}} is used to set up and frame the situation throughout the plot, this trope will emphasize the importance of the scene more, while the ChekhovsClassroom will often be presented more as background. Also, Lectures as Exposition often tell the viewer things they need to know ''immediately'' or things they needed to know two scenes ago.

For similar tropes, see {{Infodump}}.


[[folder:Anime & Manga]]
* Chapter 5.5 of ''Manga/ACentaursLife'' is about a teacher giving a primer on [[VertebrateWithExtraLimbs how evolution went]] on this AlternateUniverse, giving birth to the [[OurCentaursAreDifferent various]] [[OurMermaidsAreDifferent human]] [[FaunsAndSatyrs sub]]-[[WingedHumanoid species]] and how this made racism even a worse problem than in our world.
* Happens in the first episode of ''Anime/EurekaSeven''.
* Happens in the first episode of ''Anime/GunslingerStratosTheAnimation'' to explain (sort of) how Japan became fragmented due to the rise of the megacorporations.
* In ''Anime/{{Mnemosyne}}'', some BackStory about the Tajimamori and the "Fruits of Immortality" are filled in during a lecture at Mishio's high school. Notably, the lecture is on the topic of legends and myths but turns out to consist of [[AllMythsAreTrue pretty accurate truth]].
* Subverted in ''Anime/NeonGenesisEvangelion'': it turns out the teacher's expository teaching is [[spoiler: the government's cover-up version of the backstory]].
* One entire episode of ''[[Anime/RODTheTV Read or Die: the TV series]]'' is devoted to a character writing the Exposition Lecture that another character has to give.
* In ''Anime/YukiYunaIsAHero'', some critical background information about the setting is delivered during Itsuki's history lesson in Episode 4.

[[folder:Film -- Animated]]
* Milo gives two lectures on Atlantis in ''Disney/AtlantisTheLostEmpire''. The first one is actually his rehearsal for a proposal to his superiors, which he never gets to give due to them suddenly changing the time that makes it impossible for him to make the meeting.
** He later attempts to give a lecture to the RagTagBunchOfMisfits with a slideshow and some plumbing metaphors, only for some of his vacation photos to get mixed in by mistake. "Hubba-hubba!"
* ''WesternAnimation/HowToTrainYourDragon'' begins with one. In the space of a 5 minute lecture, Hiccup introduces himself, the other villagers, and the different species of dragon while at the same time sounding almost like a tour guide.
* In ''Disney/{{Zootopia}}'', Judy's narration in the opening SchoolPlay fills the audience in on the history of Zootopia.

[[folder:Film -- Live-Action]]
* ''Film/TwentyOne'' has Kevin Spacey's professor character tell us about the GameShowProblem during a lecture. He is an MIT professor, after all.
* Done rather creatively in ''Film/TheBigShort''. Rather than fill the viewers in on complex financial issues through traditional exposition, the film BreaksTheFourthWall to introduce celebrities to explain them. We get Margot Robbie explaining mortgage bonds in a bubblebath, Anthony Bourdain using unsold fish to illustrate how banks handle unsold mortgages, and Richard Thaler and Selena Gomez at a blackjack table illustrating how synthetic [=CDOs=] work.
* ''Film/DeepwaterHorizon'': Not quite, we just see the practice for one. Sydney's demonstration of Mike's job for a parent career day involves shaking a can of soda up, then punching a metal pipe into it, followed by pouring honey down the pipe to keep the soda from coming out, which will show her classmates (and shows the audience) what drilling mud is and how it works.
* In ''Film/TheFaculty'', Mr. Tate starts history class by repeating the prior week's lecture from chapter 4, espousing the values of conformity among the masses for the purposes of establishing a unified state. Stan is quick to remind him that they were on chapter 5 instead, which is about individual action in society. In this case, it's Mr. Tate himself who's the subject of the foreshadowing as much as the content of his lecture -- he and the other teachers are controlled by alien {{Puppeteer Parasite}}s who are trying to [[AssimilationPlot assimilate humanity]].
* ''Film/TheFinal'' opens with a {{high school}} history teacher describing how [[ImperialChina the Han Dynasty]] would sometimes [[CruelMercy leave their defeated enemies alive, disfiguring them]] in order to serve as an example to those who would oppose them. Guess what a group of pissed-off teen outcasts do with this knowledge...
* This is how we learn the main complication in ''Film/GiveMyRegardsToBroadStreet'' -- in a board meeting.
* {{Subverted}} amusingly in ''Film/IndianaJonesAndTheLastCrusade''. Dr. Jones is showing giving a lecture on archaeology, but he merely makes the point that archaeology is not about journeying to exotic lands and following ancient maps to lost cities, "and X never, ever marks the spot." Since this is Indy, however, he [[AdventurerArchaeologist definitely does not go on to practice what he teaches]] -- and he even references the lecture later with a wry grin when it turns out that [[XMarksTheSpot X does mark the spot after all]].
* In ''Film/{{Knowing}}'', Nicholas Cage's character gives some basic information about the sun and the fate vs. free will philosophies during his college lectures.
* OlderThanTheyThink: This trope shows up in ''Film/TheLastWillOfDrMabuse'' by Creator/FritzLang from 1933.
* ''Film/TheRite'' has Father Lucas explaining the basics of exorcism in lectures at the beginning of the film.
* ''Film/{{Serenity}}'' starts out with one of these (a teacher giving a history lecture to a group of young children).
** It isn't clear from the very beginning due to the matryoshka-doll-like {{Framing Device}}s at work, though.
* ''Film/ShatteredGlass'' is about former journalist Stephen Glass and his now-notorious career as a fabulist for ''The New Republic''. It includes as a FramingDevice several scenes in which Glass is telling a class of journalism students about his career for TNR. Besides presenting basic plot exposition, Glass' talk explains the fact-checking process at a magazine and illustrates how Glass got away with his fictions (in short: the main fact source was the reporter's notes, which Glass fabricated).
* In ''Film/{{Species}}'', Fitch gives a lengthily exposition of the SETI project and the failed DNA experiment to the summoned group in his boardroom.
* ''Film/{{Stargate}}'' opens up with Daniel Jackson giving a lecture on why he believes the ancient Egyptians did not build the great pyramids. The people listening to him all walk out at the ridiculousness of the theory. In a radical plot twist that surprises no one, he was right.
* ''Film/TransformersFilmSeries'':
** A class presentation but one not from a teacher, Sam attempting to sell his stuff at Show and Tell in ''Film/{{Transformers}}'' when told to give a lecture on his ancestors as part of his grade. However, he is distracted by Megan Fox doing that weird thing she does with her teeth.
** In ''Film/TransformersRevengeOfTheFallen'', Sam has a "full-blown meltdown" in the middle of the first day of astronomy class, and ends up [[MotorMouth babbling at breakneck speed]] about [[ChekhovsGun various things]] that become important later on in the film.
%%* Jean Grey at the beginning of ''Film/XMen1''.
* ''Film/UrbanLegend'' tells us about, well, {{urban legends}} by means of a lecture given in a college classroom.

* In Creator/DanBrown's book ''Literature/TheLostSymbol'', Robert Langdon lectures his symbology class on the secrets of Freemasonry.
* The ''Literature/HarryPotter'' series occasionally uses these (in addition to [[ChekhovsClassroom Chekhov's Classrooms]]). For instance, Professor Binns' ([=McGonagall=] in the movie) retelling of the Chamber of Secrets legend and Moody's demonstration of the Unforgiveable Curses.
* In ''Literature/TheNameOfTheWind'', this tends to be the way the reader learns more about the world. It's occasionally presented as a story or myth, instead.
* ''Literature/TheAssassinsOfTamurin'' teaches the reader the history of the ConstructedWorld via a session of the heroine's history class.
* The FunctionalMagic of the ''Literature/{{Mistborn}}'' series, allomancy, gets explained to the readers through Kelsier's lessons to Vin.
* In ''[[Literature/HonorHarrington Ashes Of Victory]]'', Honor Harrington has been assigned shore duty as a MilitaryAcademy [[VeteranInstructor instructor]] while she recuperates from ([[MadeOfIron extensive]]) injuries she suffered in the previous two books. We are treated to a number of such lectures, including one where a junior officer mortifies a group of awe-stricken midshipmen by calling Honor's tactics in a recent operation horribly reckless, stating that she only came out alive because the enemy simply wasn't paying attention that day.[[note]]They don't know what the readers know: This junior officer is a long-time friend of Honor's, going all the way back to the two of them being room mates at the Academy. And Honor is more than willing to own up to her own poor judgement.[[/note]]
* A teacher in ''Literature/StrengthAndJustice: Side: Strength'' educates the reader on the history of the city in the form of quite a large {{Infodump}} taking up several pages.
* In Theodore Judson's ''Literature/FitzpatricksWar'', the general history of how the world turned into a post-apocalyptic steampunk Neo-British Empire-dominated dystopia is recited in a verbal exam by the novel's protagonist, Robert Mayfair Bruce. Coincidentally Bruce was shocked to have gotten such an easy topic.
* ''Literature/{{Pharaoh}}'' has quite a lot of fleshing out of the AncientEgypt setting, some of it in lecture form.

[[folder:Live-Action TV]]
* ''Series/BreakingBad'' gives us a scene where Walter White, a chemistry teacher, describes how energy can either be released gradually and unnoticeably or suddenly and violently... [[spoiler: and in the episode's climax, uses mercury fulminate, the explosive he described in class to successfully threaten a violent drug lord]].
* ''Series/BuffyTheVampireSlayer'' did it in "Hush", where everyone's voices have been stolen. Giles delivers the exposition through transparencies and mime.
* ''Series/DoctorWho'': At the beginning of [[Recap/DoctorWhoS36E5Oxygen "Oxygen"]], the Doctor delivers a lecture on the dangers of the vacuum of space. Of particular note is his description of how long you'll take to pass out, and his mention that the fluids of the eyes will boil. Bill gets to experience some of those symptoms when she's exposed to the vacuum of space without a helmet, and the Doctor [[spoiler:winds up blinding himself when he has to give Bill his helmet so she'll survive a spacewalk]].
* The ''Series/EnemyAtTheDoor'' episode "The Raid" is about a British commando team raiding a German radar installation during World War II. It happens to coincide with an inspection tour by the German brass which begins with a lecture from the officer in charge of the installation to impart the necessary information about the installation's function to the visiting officers and to the audience.
* ''Series/GameOfThrones'':
** Maester Luwin teaches Bran of the various Houses vying for power in Westeros, which also serves to educate the audience on the matter.
** Sansa gets quizzed by her septa about the history of the Seven Kingdoms.
* Happens frequently in ''Series/{{Hannibal}}''. When he's not [[TheProfiler profiling]] for the FBI or getting psychoanalyzed by Dr. Hannibal Lecter, Will Graham is a lecturer on profiling and criminal psychology at the FBI academy. His lectures flesh out the show's backstory or the psychology behind the case of the week, and occasionally provide MythologyGags or {{Foreshadowing}} (i.e. the time he lectures on the killer of the week [[spoiler:to a hallucinatory class, foreshadowing his mental illness]]).
* ''Series/MurdochMysteries'': Late in "Big Murderer on Campus", Murdoch is in a university classroom giving a lecture on the "applied physics" of execution by hanging. The lecture turns into [[spoiler: a means of pressuring one of the accomplices to a murder into confessing against the other--the soon-to-be-infamous James Gillies]].
* On ''Series/RelicHunter'', Sydney was telling her class about a particular Indian tribe's mysterious shift in culture right before she went out and solved the mystery.
* ''Series/StargateSG1'': Jack O'Neill's young clone lectures a class of pilots on the F-302.

* In the first scene of ''Film/AbeLincolnInIllinois'', a teacher is giving young Abe a lesson in grammar -- using the text of a Daniel Webster speech as material. The audience is thus given a little lesson on secession and state's rights as political issues.

[[folder:Video Games]]
* The opening of ''VideoGame/FinalFantasyVII'' combines this with a solid EstablishingCharacterMoment. Barret asks Cloud, who has just joined Barret's group, if he's familiar with Mako reactors, and -- despite the fact that Cloud tells him that he is -- starts lecturing him about what Mako reactors are. Cloud's understandably annoyed reaction causes Barret to get pissed off with him, and they continue bickering for the first couple of hours of the game.
* ''VideoGame/GabrielKnight: Sins of the Fathers'' has Gabriel attending a lecture at Tulane University early in the game where he learns some important concepts and terms relating to Voodoo.
* ''VideoGame/GodEaterBurst'' has several cutscenes of Dr. Sakaki briefing the PlayerCharacter, [[{{Keet}} Kota]], and [[ActionGirl Alisa]] on the nature of the Aragami. Justified as the main characters are all new recruits, with you and Kota hinted at not having had much of an education at all, and Fenrir wants to spread around its institutional knowledge so nobody leaves too big a hole if they die suddenly.
* ''VideoGame/TalesOfSymphonia'' introduces its ClicheStorm plot in this only moderately clichéd way.

[[folder:Web Animation]]
* In ''WebAnimation/IfTheEmperorHadATextToSpeechDevice'', this is how the Emperor delivers an {{Infodump}} about humanity's history not covered by the Imperium's history records to Custodian and [[spoiler: [[HeelFaceTurn Magnus]]]], though he doesn't deliver it in a classroom but from the top of his [[DarkLordOnLifeSupport Golden Throne]].

* In ''Webcomic/AliceAndTheNightmare'', chapter two uses its university setting to give us two lectures and one practical lesson on the topic of magic systems and the history of Wonderland.
* ''Webcomic/BobAndGeorge'' [[ As a flashback.]]
* [[ This]] ''Webcomic/DumbingOfAge'' - Leslie's Gender Studies lecture gives background on the current storyline. The AltText [[LampshadeHanging lampshades]] this.
* Thomil of ''Webcomic/{{Juathuur}}'' [[ shows us how it's done.]]
* Amical teaches his seedlings magic in ''[[{{Webcomic/Morphe}} morphE]]'' using [[ morning magic lectures.]] They serve for exposition, world building and catching readers who do not play World of Darkness up on lore.
* One ''Webcomic/TalesOfTheQuestor'' side story was a classroom lecture about the setting's MinovskyPhysics. (In the storyline, it functioned as the first step in DoingInTheWizard.)

[[folder:Web Original]]
* A favorite technique in the ''Literature/WhateleyUniverse'', since it's set largely in a SuperheroSchool. We've seen lectures on supersuit design, several kinds of superpowers, strategy and tactics, the (made-up) physics behind this universe, how magical contracts work, and several other things.
* An chapter of ''Literature/{{Brennus}}'' is about an "Introduction to Metahuman Studies", providing an {{Infodump}} on superpower classifications. This is [[JustifiedTrope justified]] by the creation of a new superpower classification system, and so the characters, as well as the reader, have to be informed.