So you have a cruel, mean, bully of a teacher, that's got to make school life pretty harsh right? Well it could be worse, they could actually be evil.
This includes Mooks and Murderers whose day job is teaching, all way up to Big Bads who pose as teachers as part of the Masquerade. Not too uncommon in Wake Up, Go to School, Save the World situations, but can also appear in other works which are set in a school or University.
Sometimes this does overlap with the Sadist Teacher but it isn't too uncommon for some iteration of supposedly "nice", and/or well liked, teacher to be secretly evil. Perhaps so secretly even they don't know.
If they don't like teaching, a Sadist Teacher can result. If they do like it, they'll often end up a Badass Teacher. The faculty at an Academy of Evil is this by default, but in that case, their students are usually just as evil.
Also not to be confused with Evil Mentor, who is not only evil, but also corrupts his disciples with evil teachings.
- Harumi Saotome of the Higa team in The Prince of Tennis. This is the guy who actually orders his pupils throw balls at the rival coaches to injure them, and throws tantrums when they don't go along with it.
- Kuzuki of Fate/stay night is a bit of a subversion. He's well-liked among the students, and isn't actually evil. He's just amoral and has no problem going along with Caster's plans, which involve mass murder.
- Yu-Gi-Oh had... Dear lord, where to begin?
- In the original manga, it was hard to find a teacher in Domino High who wasn't evil, or who at least wasn't a creep. The worst was probably Ms. Chono, called "The Wicked Witch of Expel" by her co-workers behind her back for the sadistic way she punished students, who was so bad that Yami actually inflicted a Penalty Game on her to teach her a lesson. And compared to most of them, she actually got off easy.
- Professor Cobra, the Big Bad Wannabe of Season 3 of Yu-Gi-Oh! GX.
- Calling Napolean (also from GX) "evil" may be a stretch; he was certainly a selfish Jerkass, but he did have some good points. Eventually, he made a complete Heel Face Turn.
- Professor Chronos was much the same.
- Then there was Professor Satou. He probably could be considered a Well-Intentioned Extremist because he felt he had to eliminate Judai, thinking that Judai (who was a hero despite being a poor student) was a bad influence on the other student. He went too far when he proved willing to let Asuka drown in order to help him win the duel, and as a result, fits the Trope painfully straight. Worst of all, he failed to realize that he was little more than an Unwitting Pawn for Cobra, and it cost him in the end.
- Ayukawa wasn't evil in the least; she was one of the sweetest members of the faculty of Duel Academy. However, when much of the cast became Duel Zombies during Season 3, she was one of the most dangerous, and probably should be mentioned.
- There was also Professor Ukyo from Yu-Gi-Oh! Zexal He really wasn't any more evil than anyone else who was corrupted by a Number but he probably deserves notice.
- Himika Akaba from Yu-Gi-Oh! ARC-V the chairwoman of LDS was a morally dark-grey variant. She attempted to take over You Show by rather predatory means of pinning an incident on Yuya, but she intends to add his Pendulum Summoning to her school network to better combat Academia. Even then, there's the relationship between her and Reira...
- Dante of the 2003 anime version of Fullmetal Alchemist. She's introduced as a kind old lady who was once Izumi's alchemy tutor, but it is eventually revealed that she is the Big Bad behind the homunculi.
- Yuu Nikaidou-sensei of Shugo Chara, who is only a teacher as it involves screening children from Seiyo Academy to see if they possess the legendary "Embryo" as their "Hearts Egg". As the best way to draw out a "Hearts Egg" is to make a child become filled with self doubt about their aspirations for life, and usually means that without outside help they get their dreams crushed and he is a Child-Hater, he's presented as evil.
- The Faculty
- Kitano in Battle Royale. Although this is almost justified by the fact that the world has gone to hell and the students are unruly to the point of stabbing him at random in the hall. He doesn't actually do anything malevolent to them until after they've left school and he enrolls them in the BR program
- Matt Dillon's character in Wild Things.
- The Assistant Principal, and the super-teachers he hires, in Korean action-comedy Volcano High.
- In Hot Fuzz, the schoolteacher is one of the members of the villainous NWA.
- Harry Potter fanfiction. Way too many people like to portray Dumbledore as a Manipulative Bastard Complete Monster who's setting up Harry as a Heroic Sacrifice to defeat Voldemort, in some cases with Dumbledore planning to take all the glory immediately after. A few fanfics also have him paying off Ron/Hermione/Ginny/whoever to be Harry's "friend" as a way for Dumbledore to spy on him.
- The Demon Headmaster kinda evident from the title.
- Harry Potter: given that it's set in a Wizarding School this isn't suprising. Most of the books had one, usually the Defense Against the Dark Arts teacher. Snape is presented as an Evil Teacher but proves not to be.
- Philosophers/Sorcerers Stone - Quirrell, though he was The Mole so he didn't act harshly to the students.
- Chamber Of Secrets - Lockhart wasn't working for the villains, but the degree of selfishness it takes to steal others' memories for fame and be willing to let an eleven-year-old die to maintain his reputation probably counts as a banal kind of evil.
- Prisoner of Azkaban - none Lupin certainly wasn't evil...well maybe for one night every few months if he didn't get his wolfsbane potion...
- Goblet of Fire - Moody (though he's Not Himself, but Barty Crouch Jr. in disguise), and Igor Karkaroff as Ex-Death Eater turned coward Headmaster
- Order of the Phoenix - Umbridge, former trope namer for Tyrant Takes the Helm, whose idea of detention involves students magically carving words into their own hands by writing lines.
- Deathly Hallows - The Carrows, who were installed by Voldemort and aren't so much teachers as anti-Muggle propagandists. They're less subtle in their prejudice than Umbridge, and even more sadistic. Umbridge tortured students herself, while they encourage their favourites to torture other students.
- Agatha Trunchbull in Matilda isn't just a Sadist Teacher, it becomes obvious at the end that she probably either herself murdered Miss Honey's father/her brother-in-law or at least had him assassinated.
- Coach Gengis - who is really Count Olaf in disguise - from A Series of Unfortunate Events. (Not spoilered because... well, it's Count Olaf we're talking about).
- The Guardians of Time trilogy tries to do this and fails miserably.
- As does The German Harry Potter/The Neverending Story/The Lord of the Rings knock-off The Laura Cycle
- On of the Diamond Brothers novel Public Enemy Number Two has Sadist Teacher Mr. Palis turn out to have been "The Fence" all along
- Madame Morrible from Wicked. Both the musical and the book.
- Miss Gaunt in Ghosts of Fear Street: Who's Been Sleeping in my Grave?.
- Vice Principal Nero from A Series of Unfortunate Events is a true sadist. He makes Sunny (A BABY) work as his secretary, punishes people by taking away silverware and tying people's hands behind their backs during lunchtime.
- The Teacher From The Black Lagoon and its many, many sequels would qualify as the best example if The X Files hadn't taken that honor. "This is a whole boy. This is half a boy. Now you've learned fractions."
- Mrs. Gorf in the Wayside School series, who turned students into apples. There were several other evil teachers as well.
- Vice-Principal Chapman from Animorphs, who's high up in the Yeerk front organization The Sharing (which is similar to a scouting group or something) and often tries to recruit students, including the protagonists. He acts like a nice guy, though.
- Salamander features Maridon, one of the teachers in the story's College of Magic. He's not presented as a bad teacher, just as a teacher who wants to be a Person of Mass Destruction.
- Professor James Moriarty.
- The Young Bond novel Blood Fever has Professor Peter Haight, who appears to be a Reasonable Authority Figure but it as actually a member of a secret society dedicated to restoring the Roman Empire and who poisons the teenaged James Bond when he gets to close to the truth.
- Power Rangers Dino Thunder - Principal Randall aka Elsa, The Dragon to Big Bad Mesogog... who, in his civilian identity, would also briefly try his hand at teaching when Dr. Tommy Oliver is out.
- Half the faculty (including a few dinner ladies) in the Doctor Who episode "School Reunion".
- The Sarah Jane Adventures story Revenge of the Slitheen.
- Buffy the Vampire Slayer - "Teachers Pet"
- In season four of Buffy, there was the Knight Templar Psychology professor Maggie Walsh.
- Ms. Paddock from the second season X-Files episode "Die Hand Die Verletzt". She actually is a manifestation of demon Azazel.
- He's only briefly a teacher, but Cromartie from The Sarah Connor Chronicles
- In the Outer Limits episode "The Special One", Mr. Zeno, an alien in human form, tutors gifted children, planning to indoctrinate them and use their advanced scientific skills to help his planet conquer Earth. Zeno kills one father who discovers what's going on, and almost kills another before his current pupil (the son of Zeno's intended target) turns the tables on him.
- In Smallville Brainiac mixes this with Badass Bookworm, Complete Monster, Evil Mentor, and Omnicidal Maniac. No he's not your average History Prof.
- The headmaster Mr. Finch and the new staff he installed in the Deffry Vale School in the Doctor Who episode "School Reunion".
- Persona 4 has Mr. Morooka, a.k.a "King Moron", a rather snobbish (and hideous) man with a grudge against women as well as the main character. He treats his students rudely (putting the main character on his "Shit List" within minutes of meeting him), and has a tendency to get drunk on school fieldtrips. He ends up murdered about half-way through the game.
- In this trailer for WildStar, the android teacher is rather cruel in her vivid descriptions of the brutal, gory deaths her students will likely suffer on Nexus, but then offers them an alternative (as in, a Mercy Kill.)
- Aaahh Real Monsters had The Gromble.
- Courage the Cowardly Dog: Episode 52 Part 2: "Perfect" had a mysterious old teacher approaches him, and strictly trains him into becoming a perfect dog.
- Denzel Q. Crocker from The Fairly OddParents slides from a simple pathetic Sadist Teacher to truly evil depending on the episode. Compare the Sympathetic POV Crocker in "The Secret Origin of Denzel Crocker!" to the maniacal dictator he becomes in the Made for TV Movie episode Abra-Catastrophe!.
- Headmistress from Mucha Lucha
- Invader Zim had Miss Bitters.
- X-Men: Evolution has Bayville High's Principal Darkholme that is, Raven Darkholme, a.k.a. Mystique. Kelly was no slouch, either, especially after mutants were exposed.
- Miss MacBeth from Invisible Network of Kids.
- Mr. Strickler from Trollhunters although in his defense, his evil deeds have nothing to do with his teaching. He actually comes across as a generous and kind teacher to his students.
- Principal Bump from The Owl House straddles the line between a Dean Bitterman who happens to be a wizard to this Trope. In his first appearance, he tried to dissect Luz to see if she was human, and his methods of discipline are rather... extreme. on the other hand, he was willing to admit Luz to the school later (after confirming Luz was human) so long as Eda undid all the damage she did when she was a student.