Chapter Text
Five years have passed since Izuku started getting mentored by Nedzu, as well as various other pro heroes, and he’s finally getting to attend Yuuei. As a teacher.
Given that he recently graduated college, and that he got his hero license last year, it would serve no purpose for him to return to high school as a student. This, alongside the fact that the last heroics teacher recently retired, and the new one has absolutely no experience, leads to his current predicament of having to teach a class.
Since he’s still only 15, he figures that the best way to introduce himself was to pretend to be a student. Kan, ever the spoilsport, denied his request to pretend to join his class, so Izuku recruited Hizashi and they bothered Shouta until he agreed.
When the school bell rings to show that homeroom is beginning and the students begin to file in, he takes a seat, waiting for Shouta to roll in. Then a different familiar face comes through the door and collapses of a seat, putting his feet up on the desk in front of him. Thankfully Katsuki’s unique mix of a god and inferiority complex prevents him from looking too closely at the other members of his class.
Then to Izuku’s complete and utter joy, Tensei’s younger brother starts scolding the blond Pomeranian that made his life hell, and of all things about the desks. He knows he probably should tell the sonic knockoff that last week he tried to turn those desks into transformers, but decides that it would give away his cover a bit too quickly. Besides his older brother probably made some random-ass rule up about how disrespecting them means expulsion, and the last thing Izuku wants to do is ruin his friend’s fun.
Shouta crawls in a moment later, and like almost every other year, he’s in his giant yellow sleeping bag. Izuku turns to the person next to him, a girl with brown hair and somewhat unusually large finger pads. Touch-based quirk. “Well, that’s certainly a large caterpillar”. Shouta then somehow maneuvers into an upright position, unzipping and stepping out of the bag. "And now the butterfly emerges from its cocoon"
“I’m Aizawa, your new homeroom teacher. Get changed into your gym uniforms and go outside for a quirk test, anyone who isn’t out in ten minutes is expelled” some of the students start groaning, obviously not believing that he’s serious, “I’m not kidding, time just started” With that, they start to sprint out.
Aizawa catches him a few seconds before he makes it through the door, “This includes you, problem child, if you want to pretend to be my student, then you get treated like one.”
Izuku knows that this one is a logical ruse, but Shouta would undoubtedly ruin his fun if he complained.
So he steals the emergency uniform (for quirks that tend to be a bit hazardous to cloth) and heads outside. Due to him not sprinting he ends up being one of the last ones out, earning him a glare from the Ingenium knockoff.
Shouta then proceeds to call out Katsuki to demonstrate the ball throw. He proceeds to use an explosion to launch the ball ten times further than his old middle school record. While others may have frightened by this display of power, Izuku can already think of about 15 different things he needs to improve upon.
The other kids begin to speak about how fun this looks, which provides the perfect opportunity for Shouta to set forth his first real expulsion threat. He says something about how they’re not here to make friends and have fun, but Izuku drones him out, preferring to figure out what tools he can use to blow everyone else out of the water.
Besides Shouta’s a huge ass hypocrite, he married his friend from Yuuei.
The first event is the 50-meter dash.
Tensei’s younger brother easily surpasses most of the other kids, and Izuku can’t really think of any way to improve his time except for practice speeding up.
Yaoyorozu is his current favorite though, as she shows an almost complete mastery over her quirk, as well as having the creativity to back it up. Her score also shows it, as roller blades are harder to beat than one would expect
Most of the other kids could easily improve their scores with a little ingenuity, support Items, and a lot of practice, for example, Uraraka with a grappling hook would be almost unbearably fast.
When it’s almost his turn, he goes to the “magic” bag, also known as the home of a frightening amount of Hatsukubabies™. He digs through it searching for one specific invention.
Finally, he finds it, his supersonic jet pack. The product of far too many caffeine-fueled all-nighters between him and Mei, capable of accelerating to 100 mph in less than 10 seconds.
He easily comes in first.
The rest of the tasks go in a similar fashion. He makes mental notes of how to improve the student’s quirks, then proceeds to destroy their scores with one of his inventions. It’s almost sad.
Surprisingly, Bakugou doesn’t seem to recognize him, who knew his inability to remember names would come in handy for pranks. It also probably helps that Hizashi pranked him by dying his hair neon yellow earlier that week.
The tests and relatively quickly. Izuku’s in first, to nobody’s surprise. Then Yaoyorozu, who he’s currently planning to kidnap and introduce to Mei. Her quirk is honestly perfect for an inventor, and maybe Powerloader will finally allow them to use the more expensive materials since the price would be less of an issue.
In the last place is somebody named Mineta. Who promptly gets expelled, much to the relief of the girls as well as Izuku. Anybody who decides to focus more on harassing girls than trying to be a hero has no place in Yuuei.
The next day, it’s time for him to reveal himself as a teacher. The yellow in his hair has finally washed out, so his ex-childhood friend might actually recognize him. To prevent this he decides to wear one of his many All-Might beanies.
Stepping into the classroom with it on immediately draws the attention of Iida Jr. “That Hat Is Not Part Of The Yuuei Uniform”
His response, “I have a note from a teacher saying I can wear it, plus there are no regulations on hats” Technically he is the teacher, and the note only says ‘I can do what I want - Theorem’
Thankfully Iida doesn’t ask to see it, only deflating at the correction.
The other students in class 1-A soon arrive, filling up the classroom. This time they quiet down the second a yellow sleeping bag appears.
Shouta quickly takes attendance before curling up in the corner to sleep. Homeroom only lasts for 10 more minutes, then his class begins. It’s finally show time.
He grabs his “magic” bag and begins his preparations. It took an all-nighter and a near-fatal amount of caffeine, but he managed to write a quirk assessment on every student in 1-A.
He waits a few minutes after the bell rings, just until the whispers of “where is the teacher” start to turn into “if they’re not here in 15 minutes we can leave”, before standing up.
Uraraka turns to him, “Hey, what are you doing? Sit down. The teacher’s probably coming in a moment”.
At that Izuku dramatically whips off his hat, revealing the emerald green hair underneath, “Oh, but I am the teacher,”
Some kids gasp, “My name is Izuku Midoriya also known as Theorem, welcome to Intro to Heroics.” He begins to pass out the quirk folders he made, “Lesson 1. Pay attention to the people around you.”
A familiar blond rises from the back, “SHITTY DEKU, WHAT THE FUCK ARE YOU DOING HERE!” ah yes, time to confront Bakubitch.
“Hey Kacchan, I’m here because Nedzu thought I was qualified to teach” Which is probably due to the fact that the rat has basically adopted him, but it’s highly unlikely that anyone would accuse the Principle of Yuuei of nepotism.
“What did you suck his furry dick or something, there's no way he’d let a useless Deku even step foot in this building unless he was bribed” Izuku knows logically that Katsuki could make a great hero one day, but honestly he kinda wants to send in an expulsion form just to see the look on his face.
But unfortunately, if Katsuki got kicked out, Izuku would be worried that he’d try to prove that he’s the best in a far more illegal fashion. “Well, maybe it’s due to the fact that I’m currently the youngest pro-hero in Japan, and that I’ve either solved or helped solve over 150 cases in the past 3 years.”
“Stop lying Deku, you’re quirkless and quirkless people can’t become heroes, It’s common knowledge,” Now he’s getting on his nerves. It’s one thing to insult him, but to blatantly deny his accomplishments shows a level of ignorance that Izuku knows he’s going to have to beat out of him.
“Bakugou Katsuki, Shut the fuck up before I decide to expel you,” He hands the blond Pomeranian his backup file, the one that Izuku prepared just in case something like this happened. While it contains the suggestions for improvement he’s put in everyone's folder, It also shows approximately 15 different ways somebody (Izuku probably) could kill him within 10 minutes. Without a quirk.
“You can’t expel me, I have the perfect quirk for becoming a hero”
“If you say so” Izuku turns his attention to the other students in his class. “In everyone’s folders, you will find an assessment on your quirk, as well as suggestions for its improvement”
While Katsuki unfortunately, refuses to even glance at it, instead choosing to cross his arms and pout, the other students seem amazed at the contents.
Then Iida stands up and starts chopping. “Most Of These Suggestions Rely On The Use Of Support Items, Shouldn’t Heroes Learn To Rely Only On Themselves!” Tensei apparently spread his support item phobia to his brother. Izuku blames the Hatsumes.
But Izuku officially has his first problem child. “Well machines are actually far less likely to fail than quirks, given that you really can’t experience machine overuse, while you shouldn’t completely rely on them, using them often help heroes”
He takes out one of his favorite inventions, a solid light projector, and turns it on. Suddenly a copy of him appears, “anyways tell your brother that not all support item makers are like the Hatsumes, so he’s probably not going to be kidnapped again if he uses another company”
About 15 minutes into the class Izuku sends them into the gym to test out his theories.
As he walks around, he notices that Todoroki seems to be completely ignoring his suggestion to use his fire. Izuku knows that he’s the son of Endewhore, so he probably has some issues, but he wrote it in red ink. And underlined it. Three times.
Yoarashi also seems to avoid Todoroki like the plague. On the rare occasion they’re in the same area of the gym, he’s giving the bi-colored boy dirty looks and interfering with his practice. Izuku makes a mental note to confront them on it, as well as to maybe force them to pair up later in the year.
Izuku heads over to where Katsuki is training only to find that he’s literally only working on creating bigger explosions. Which probably does help, but that's one of the only things Katsuki doesn’t need much improvement in. “Hey Katsuki, you should try working on improving your precision and control,”
Unfortunately, Katsuki's just as agreeable as always “I don’t need to listen to you stupid deku. You don’t even have a quirk, how can you think you know mine better than I do?”
“Well, if you don’t want to improve, then you shouldn’t be in the hero course to begin with” While he can’t expel boom boy without the risk of creating a new supervillain, he can send him to general studies with a chance of making it back into the hero course depending on his behavior.
“I’d like to see you try” Challenge accepted.
When school ends, Izuku takes a few minutes to grab the recordings of what happened in his class and heads to the principal's office.
Nedzu agrees to the plan almost immediately and within the hour Bakugou Katsuki is officially a member of Class 1-C.