Here is one of the fruits of unhappiness; that it forces us to think of life as something to go through. And out the other end. If only we could steadfastly do that while we are happy, I suppose we should need no misfortunes. It is hard on God really. To how few of us He dare send happiness because he knows we will forget him if he gave us any sort of nice things for the moment....
Maria Graceburt from Mai-Otome intimidates most of the students (and even Headmistress Natsuki, in the manga), but she always makes sure that the rules are followed and that all students are treated fairly.
Nozomu Itoshiki of Sayonara, Zetsubou-Sensei. Once you get past the fact that he's so depressed and suicidal. He can act harsh sometimes but it's never because he bears any malice towards his class, he just wants them to understand the bleakness of the real world. Also, per the trope, he's loved (sometimes a bit too much] by all of his students (except Kaere... and that's only halfway, since Kaere's Split Personality, Kaede, is in love with him too).
Vita's a better example. While Nanoha balances a grueling training regimen with her cheerful, affable nature, (even letting the recruits call her by her first name) Vita, by her own admission, hardly ever compliments the students and is quite quick to berate them for their mistakes or what she sees as stupidity, but at the same time, cares deeply for their development and is described as kind at heart.
Unforgettable is how she verbally trashes Teana after trying something way too dangerous that would almost have hurt her partner Subaru.
Nitta of Mahou Sensei Negima! is generally shown acting like this. It's partially subverted later on, as outside of class activities he's actually a pretty nice guy.
Fate Averruncus becomes this when he takes over 3-A's class. Fans have described him basically as a Trolling Teacher.
One of the teachers in Azumanga Daioh is this kind of teacher, scolding the entire class for not doing their homework, but deciding to go easy on Chiyo-chan because she is younger and obviously scared by his style of teaching. He only appears once, leaving Yukari, Nyamo and Kimura to be the main three teachers in focus during the show.
Austria of Axis Powers Hetalia was one of these, particularly towards Chibitalia, giving "her" plenty of hard work to do. But Austria isn't all that bad, as he did allow Chibitalia a day off when "her" first love Holy Roman Empire had left and he saw that Chibitalia had tears in "her" eyes... and willingly took up "her" share of work
Izumi Curtis in Fullmetal Alchemist is the embodiment of this trope. She becomes almost like a replacement mother to Ed and Al.
Piccolo in Dragon Ball Z when he eventually warmed up to Gohan (who admitted he was a better teacher than Goku, who was too soft). No such luck with Goten and Trunks though, since by the time he had to train them up they were in the middle of the Buu crisis.
Goku did get a bit better about being too soft after he'd experienced becoming aSuperSaiyan. Compare Goku's utter lack of training methods in the Saiyan Saga, to him training Gohan in the Cell Saga, then him perfecting it right around when he begins to train Uub.
Coach Kamogawa from Hajime No Ippo is a very grumpy old man who's not above hitting his boxers (especially Takamura) for screwing around. He's still a good guy that cares very deeply about them.
The Principal from Yandere Kanojo. Has no problem with hitting (or, hell, brainwashing) delinquents, but treats everyone who follow rules nicely (even "redeemed" delinquents) and being fair toward all of his students.
Hardscrabble from Monsters University, while the head dean, was an example of this. She expressed a great deal of Tough Love to the lead characters, mostly because she didn't believe in their potential.
Minerva McGonagall is so strict that she tends to subtract more points from her own students when they do wrong because she holds them to higher standards. So beloved that Harry was able to summon up the hatred necessary to perform the Cruciatus Curse when Alecto spat in her face, which is something he couldn't even do when his own father-figure was killed.
Madame Hooch is another, mostly forgotten example. Since her subject (broom-flying) is so dangerous, the penalty for breaking rules in her class is expulsion. Not point loss or detention. Expulsion.
Madame Hooch (movie version): If I see any brooms flying around while I'm gone you'll be out of Hogwarts faster then you can say 'Quiddich'.
Severus Snape walks the line between Stern Teacher and Sadist Teacher, taken all in all. He heavily leans toward Stern Teacher with fellow Slytherins, walks the tightrope with Ravenclaws and Hufflepuffs, nearly falls over into Sadist Teacher for Gryffindors and bloody well swan-dives off into the black wherever Harry, Ron, Hermione or Neville are concerned.
Susan Sto Helit from the Discworld novels becomes one of these in Thief of Time, contrasting highly with the wishy-washy other teachers at Madame Frout's school. Having cool powers probably helps.
Mr. Perboni from the Italian novel Heart by Edmondo D'Amici. He scares the crap outta male lead Enrico and the other kids when he comes into the classroom, but his fatherly behavior towards them makes him very well-loved soon.
Muriel Spark's The Prime of Miss Jean Brodiesubverts the trope all to hell, specifically the "tough but fair" part. Miss Brodie deliberately designates one of her girls as a "stupid" victim, marking her for life. She's a charming, intelligent, and vivacious fascist.
Melissa "The Schoolmarm from Hell" Mailey in Eric Flint's 1632 series. Her tough-but-fair approach is lampshaded at one point with a complaint to the effect of, "Who cares about 'fair?' So she makes us all read this crap equally and with no favoritism! Big deal." Also once made then-teenaged roughneck Harry Lefferts write "I will not be a smartass in front of a way smarter teacher" 200 times on the blackboard; an older Lefferts later admitted, "I was being a smartass, and she is smarter than me."
Prince Nigel Haldane, Duke of Carthmoor in the Deryni novels of Katherine Kurtz. The "Iron Duke" trains the pages in the royal household, and he's generally called "tough but fair".
With pages in a royal hunting party in Deryni Rising: "No, no, no," Nigel was saying. "If you ever address an earl simply as 'Sir' in public, he'll have your head, and I won't blame him. And you must always remember that a bishop is 'Your Excellency.' Now, Jatham, how would you address a prince of the royal blood?"
In The King's Justice, he's shown training two young pages in the rudiments of riding, catching one boy by his tunic and belt when he falls and putting him back on the warhorse: "They [Kelson, Morgan and Dhugal] could not hear what Nigel said to the lad, though his words brought an immediate flush of scarlet to the downy cheeks."
Xanthos, nicknamed Xanthippos, from Detectives in Togas. But even if he scolds the boys permanently, he's still on their side, always.
At Tyentyetnikov's school in Dead Souls. Sadly, this great teacher passed away before Tyentyetnikov would do his courses, which is blamed for his incompetence in life.
Mr. Turner seems to be this at first when he gives the kids a tough assignment, causing Cory to call him "Feeny with an earring." He mellows out into a Cool Teacher, however.
The CBBC gameshow Raven's titular character is this. He's pretty stern, makes his 'students' (so to speak) jump off high trees, swim through freezing lakes, solve riddles and puzzles, pits them against 'demons', and if one's unlucky enough to be in last place, they have to go through what can only be described as the lovechild of Scrappy Level and Nintendo Hard. If they do well however, he praises them, and treats those who have to leave with dignity.
Ms. Kwan from Degrassi The Next Generation fits this role. She's very stern, not letting any talking in the class go uninterrupted (her interjections are sometimes humiliating), taking Spinner's Walkman from him (and breaking it in the process), and other similar things. Spinner and Jimmy grow tired of it in Season 1, and play a series of pranks that escalate quickly and end with Ms. Kwan taking a leave of absence. Eventually the two learn that her husband was very sick at the time, and come to realize that even their teachers are humans. Ms. Kwan and Spinner have a friendly relationship after she returns that lasts the rest of the series (even after Spinner is forced to retake her class). As time goes on, we discover that, despite her stern nature, she cares about her students very much and often is quite lenient, bending the rules to allow students extensions or do-overs quite often. Plus, her class is very creative and involves much creative writing and performing plays and scripts.
It looks as though "Snake" Simpson has been pushed into being this in Season 10 by students' behavior in the first couple of months of his principalship. Hate-crime assault, a spiralling vendetta leading uncomfortably close to attempted murder, and near-prostitution and rape (the last three on the same night) will do that.
The title character in the Japanese drama 3-Nen B-Gumi Kinpachi-sensei.
Most of the teachers in I Carly, especially Howard and Briggs, fits this trait but they’re not necessarily evil because they apparently there are lows they won’t go unlike some of the others does.
Subverted in the Key & Peele "Substitute Teacher" sketch. Mr. Garvey, the title character, is a veteran inner-city teacher shown taking over a class of bored, mostly white suburbanites. He reads their names off the roll as if they were Ghetto Names (inverting that trope in the process), and gets extremely confrontational when the students gently correct him, even sending one to the principal's office, assuming that they're just giving him attitude.
Mrs. Olsen from Frazz is this underneath her general meanness.
Dr. Ting (Paige's biology teacher) from FoxTrot. Also, Peter's unnamed physics teacher.
Clara Godfrey from Big Nate runs a tight ship and has zero tolerance for the title character's antics, but seems to have a good relationship with her other students. Nate sees her as a Sadist Teacher, naturally.
Kuzuki of Fate/stay night. It's noted that he plays an excellent balance to Taiga. Unfortunately, he's also an assassin at heart (if not practice... possibly) and the Master of Caster, so he only survives in one route. Where he isn't even revealed.
Instructor Aki in Final Fantasy VIII will lower a SeeD's rank when they're caught committing an offense within Balamb Garden. There's a reason why most players would miss him the entire game. Slightly subverted in that nobody likes him.
Aoi Matsumura seems to be the only teacher at Kisaragi School to take her job seriously.
Raine Sage in Tales of Symphonia is noted for being cool, strict, and practical, and even smacking her students around when they're being particularly stupid. Which makes it a very sweet moment when, late in the game, she admits that she's so hard on the hero in particular because she knows he's strong enough to handle it, and wants to see him grow up strong.
Serah becomes one between Final Fantasy XIII and Final Fantasy XIII-2, at least that's how she's described by the kids of New Bodhum. You actually get to see her display a bit of this during the story, where she gives a stern lecture to miniflan after beating them in battle in the Sunleth Waterscape 400 AF.
Duncan in Dragon Age: Origins, which can even be invoked by the Warden mentioning that their first impression of him was that "he's firm, but fair". However, it's also shown on a few occasions that Duncan does occasionally let his humour show through.
Himuro Reiichi in Tokimeki Memorial Girl's Side 1 is very stern indeed - in addition to being the protagonist's homeroom and math teacher, he's also the advisor of the school's brass band, and where any other club will allow you to miss two mandatory practices, Himuro will kick you out if you miss even one. True to the trope, though, he's also genuinely committed to helping his students learn and takes real pleasure in seeing them succeed, which is one of the reasons (the other being his good looks and sexy voice) that he's so popular at Habataki High School in spite of his strictness.
Professor Dominic Deegan, during his short stint as a teacher. He warmed up a bit, too, after he learned his vision/prediction that half of his students would drop his class didn't come to pass, and actually gained a new student in the process.
Mr Raven in El Goonish Shive is an extreme example, to the point where he initially came across as a Sadist Teacher. What keeps him in this category is that he doesn't arbitrarily pick on students because he dislikes them (in fact, the students he's hardest on are the ones he thinks have the greatest potential), he attempts to do what's right for his students (not always correctly, such as thinking Grace needed to be in a remedial class) and he will defend the school and its occupants with his life, if necessary.
Several teachers at Whateley Academy in the Whateley Universe. Mr. Ramirez, who teaches intro Spanish; Dr. Yablonsky, who teaches the lab for Powers Theory and has been likened to a forcibly-retired Batman as a teacher; ... All these people were probably really tough superheroes in their prime.
The martial arts teachers, too, especially Ito-sensei, who seems to be one of those teachers that really pushes his students' limits.
And he's a Badass Normal who can kick most of his superpowered students' asses.
Mr. Ratburn from Arthur was one of these, though the stories about him before we meet him make him out to be a Sadist Teacher. Several episodes of the show, most notably the one where his sister, a Misplaced Kindergarten Teacher, substitutes for him, show how having a Stern Teacher can (sometimes) be a good thing.
Mr. Fugue, Arthur's piano teacher, was also thought as a Sadist Teacher but was this trope instead. It showed again when he taught Arthur's music class.
Mr. Barkin in Kim Possible seems to be somewhere between this and Sadist Teacher; no one thinks he's really that bad of a guy, but they wish he'd be less of a hardass.
Doug: Mrs Wingo, "You're knocking on trouble's door."
Same with Mr. Bone—though at first glance he seemed like a Sadist Teacher, he was more of this than that. You just need to catch him on his good side.
He recognized that kids often need a firm hand, but was also willing to listen to reason when it was pointed out to him, and given that Principal Buttsavich was nowhere to be seen Mr. Bone often had his hands full.
In Doug Battles the Rulemeister, Bone, an assistant principal mind you, points out that since he's at a higher position than him, Buttsavich can talk about him with or without his knowledge or present, implying he can overrule a decision by a staff member, Bone included, depending on the situation. Doug uses this knowledge when Bone catches making him of him in a comic. However, it's returned after Doug inform that he broken a rule. While Bone may be viewed as harsh, he admits that he too is subject to the same school rules as Doug, his classmates, and the teachers.This could also imply Buttsavich could be subject it to them as well, although it's unclear since he's never seen.
Dr. Pappas from Growing Up Creepie: He's always spying on Creepie and the other students at Middlington Middle School. Dr. Pappas never cuts anybody a break if they're late turning in a class assignment or home work. Dr. Pappas is a stickler for rules. Though strict he has shown he does care for his students, especially Creepie a.k.a. Miss Creecher.