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Operant conditioning is a type of associative learning process through which the strength of a behavior is modified by reinforcement or punishment .
It started when they were children. In order to keep some semblance of friendship between him and Katsuki, Izuku had begun to give his blond friend spicy candy whenever they got along. He stored these candies anywhere he could– in pockets and backpacks, in the cupholders of his car seat and even in his laundry basket. Anywhere Izuku knew Katsuki might be, he made sure he was ready. If Katsuki behaved himself, Izuku would grab his hand and place a piece of candy to his palm.
As the two aged, and Izuku was found to be completely quirkless, he gave the candies out less and less. During middle school, the candies would show up in desk cubbies and backpacks– a new one every few months during the first half of the school year– only when Katsuki had picked on him less on certain days.
Shouta Aizawa had about had it with his hell class. With the exception of Midoriya and his extensive hospital stays, they were all shining examples of perfect attendance records and A++ students. Even Kaminari, who played the role of stupid comedic relief, was excelling at everything taught. He had observed the way the students interacted to be able to stop bullshit before it began.
He knew that every Wednesday night, his class had a horror movie night in the common room to desensitize themselves from scary things. During that time, Sero and Todoroki would subtly scoot closer to each other until they were touching, but it was still in the air about whether it was for comfort or because they liked each other. He knew that Bakugo secretly hated horror movies, and spent an extra hour cleaning up with Kirishima before heading to his room in order to calm down. He knew that Kirishima constantly begged Yaoyorozu to make him hair dye so he did not have to buy it and that she would only say yes if he asked after curfew. He had seen Uraraka wait for Kirishima to distract Yaoyorozu long enough to sneak money from her wallet on multiple occasions, and had witnessed Tokoyami attempt to learn how to juggle multiple times, but come up one piece of fruit short each time from Dark Shadow snagging it midair and then munching down happily. One that had surprised him slightly was learning that Iida felt some sort of attraction towards Uraraka– to which he immediately began to pair them together for any kind of project. ‘Fueling the fire’, Hizashi had said. He had even known exactly what Hitoshi had been up to when he caught him sneaking back into his bedroom a month after being adopted– not that his son had been subtle about his crush on his resident class idiot.
No, what exhausted him the most was the weird relationship Midoriya and Bakugo seemed to share. He had learned from Nezu that the relationship was mostly that of bully and victim, and had attempted to stop them from interacting solely outside of training exercises. However, after a few months, Shouta noticed that the two were naturally drawn into each other. Eventually, he watched as a peculiar action began to take place. Any time Bakugo would complete a task without bullying Midoriya, a small piece of candy would appear on his desk.
Where was the candy coming from? How was it getting there? Most importantly, who was giving it to him? It took a few weeks for him to catch the act, but suddenly he understood. Midoriya would eat lunch, quietly sneak back into his classroom so as not to disturb his lunchtime nap, place a small piece of candy on Bakugos’ desk, and then beeline to the bathroom before his friends came back and caught him.
Because of this action, Shouta decided to look a little further into it. The candy smelled spicy, and he had seen Bakugo with it on his own accord before. It was no surprise that Midoriya knew what candy Bakugo would eat, the thought of them being childhood friends crossed his mind. However, what was so intriguing about this candy was the ability it had to calm Bakugo down. Shouta had seen how as soon as the candy had started to appear, Bakugo completed more and more tasks without being aggressive and loud. The more candy he got throughout the day, the calmer he was. That night, he explained his findings at dinner.
“He conditioned Bakugo into being nice.”
Shouta’s head snapped up at this. “What?”
Hitoshi stopped with his chopsticks midair, the soba noodles falling back into the bowl. He frowned before setting the chopsticks back down. “Izuku conditioned Bakugo into being nice to him. I read the journal he has about it. He gave him a lot of candy as a kid when he would do something good, then when Bakugo realized Izuku didn’t have a quirk, he stopped giving him candy due to the bullying.”
Hizashi choked on his food before beginning to laugh. “Of course he did. That's great! Wait until Nezu hears about this!”
“With your loud ass mouth, he probably already does.”
“Damage dealt, damage taken, Sho. Be nice to me.”
The next day during his class time, Shouta decided to see just how far he could push the impromptu psychology lesson. “I want everyone to raise their hands. Good. Touch your nose. Good.” He continued on this way for a few minutes, pausing in between orders to praise them. “I want you to all stand up.” Everyone stood. “Spin around.” They spun. Shouta began to notice the quizzical expressions. “Sit down.” At this point, everyone sat somewhat reluctantly.
“Aizawa-Sensei!”
“Yes Iida.”
“What is the point of this? We know how to follow directions!”
“Oh, do you now? Well, then let’s see what this lesson is all about then, shall we?” Shouta walked to the door of his classroom and let Hizashi and Hitoshi in. “We will be splitting you into two groups today. Ten people with me and All Might, Ten with Mic and Shinso. Choose your leaders, go.” Almost immediately he watched Denki jump from his seat and run for Hitoshi. “Except Kaminari, who is on my team.” Shouta kept the maniacal laughter in his head to himself as Denki slunk over to him. “Welcome to team Aizawa, Kaminari.”
“I’d be here eventually anyway sir.” Denki mumbled, but it was still loud enough for Hitoshi to choke on the drink he had been holding and for Hizashi to begin laughing. Shouta had expected the mention of All Might to draw Midoriya to his team, but was surprised to find him standing next to Hitoshi instead. He should look into that later. Instead, he found Bakugo scowling at him from behind Kirishima. Once the teams had been divided, he began to lead his students outside. As they waited for All Might, Shouta instructed everyone to sit down, following it once again with praise.
“What do you all know about Psychology?” He asked, turning to look at where his family sat beside him at the front of the group and grabbing Hitoshi’s drink. He listened through a whole list of ‘it’s brain science’ in different words, before looking up to see Midoriya with his hand raised. Perfect. “Midoriya, What’s psychology?”
“Psychology is the study of behaviors and what causes those behaviors. It’s the way our minds react to stimuli.”
“Yes, exactly. It’s the study of behaviors. Today, we are going to study your behaviors.” Shouta finally took a drink out of Hitoshi’s cup and grimaced. “What the hell is this?”
“It’s like three different cans of Monster mixed together. I think it tastes good.”
“It’s no wonder you don’t sleep, Hitoshi.” Shouta handed the cup back and Hitoshi grabbed it quickly, downing half of it in a few seconds. He then watched Kaminari make a grabby gesture at the cup, causing Hitoshi to start to crawl over to hand it to him. “No. He cannot have that. I will not be subjected to the energetic outbursts of a highly caffeinated ADHD powerbank.” Before anyone could react to that, All Might came skidding to a halt directly in front of them, coughing and hacking before feebly attempting to yell his signature phrase.
“Thanks for joining us today, thought you weren’t going to make it.” Shouta glared at his husband before turning to where All Might stood.
“All Might, you and I have group A, containing Yaoyorozu, Kirishima, Kaminari, Bakugo, Shoji, Mineta, Ojiro, Hagakure and Sato. Everyone else is with Mic and Shinso.” All Might nodded and gathered the group together, pulling them off to the side. Group A– the group who was about to be ripped to shreds. As soon as Shouta knew they were far enough away, he turned to Hizashi. “Lots of rewards, praise them, give them stickers, I don’t care. Just make sure they do better than my group.”
“Uh, Mic-sensei, what’s happening?” Jiro asked, watching her homeroom teacher walk off.
Hitoshi began to laugh, looking at his friends. “This is going to be fun.”
The test was going to be relatively simple. Both teams would run through the same training exercise three separate times. The first time, they would run it normally. The second time, they would be rewarded or punished–based on the team– for how they did. The third time, the team leaders would stay out of the field. The field had been divided in half, with each team as far away from the other as possible.
“Cover your ears for a second, listeners.” Mic stated after explaining the non-technical rules of the exercise. He inhaled sharply. “READY, SET, GO!” Both teams took off, the leaders splitting up and following them.
The first round came to an end after fifteen minutes. In Shouta’s opinion, that wasn’t bad. However, he had a point to make. Bring on round two. Again, the scream to go was heard from across the field.
As the participants of team B did something that would make them go faster, they were praised and rewarded. As team A did something that would make them faster, they were reprimanded.
“You were all too slow! You have to go faster or you’ll lose! You won’t get anywhere doing stunts like that! Why are you on the roofs! Why fly over the rubble!” The verbal barrage kept going from both he and All Might. He could see the students trying new routes to the end, lingering on decisions that got them scolded the first time. Through the earpiece he wore, Hizashi could be heard praising his team.
“Keep going guys! Great use of power Ashido! You got this Koda, keep going! Wow, That was clever Sero, you should try those moves more often!” Hitoshi could also be heard praising the five he had split off with.
“Wow you’re fast Izuku! Come on guys, you’re doing great!” Shouta smiled to himself to hear his son step into the teacher role so easily.
“We’re done Sho. Ten minutes.” Hizashi whispered through the ear piece.
“Ok, we aren’t. Meet out front.” Shouta responded, then quickly went back to scolding the students. It took twenty minutes total for Shouta’s group to finish.
“Ok guys, we’re going to run it all together this round, and the leaders won’t be with you.” Shouta said as Hizashi stood outside with his group. Looks of confusion were tossed around as group B stood with smiles on their faces and looked energized to go. Group A looked to be on the brink of exhaustion, giving up almost looked more promising. Everyone lined up at the beginning of the course, varying levels of ready to go. Shouta parked himself on the ground next to Hitoshi as Hizashi began to activate his quirk.
“ROUND THREE, GO!” Everyone took off. Hizashi sat next to his family as All Might paced around quickly in front of them.
“I think this was a harsh lesson for them Aizawa. They need to be encouraged and persuaded to do better, not worse!”
“Yeah, that’s why I’m teaching them these things. Midoriya has been using this on Bakugo since they were children, and I’ve noticed the benefits the past few weeks. Trust me on this.” Shouta thanked whoever was in charge that day that All Might stopped talking. He barely had time to refocus on Hizashi when team B came barreling out of the designated finish zone. Shouta looked at his watch astonished.
“Five minutes! That’s incredible!” Hizashi exclaimed, bouncing to his feet and running to his group. Hitoshi, who had passed out in the grass somehow–although a caffeine high followed by intense exercise isn’t recommended– slept through the commotion. Shouta was impressed. Fifteen minutes had turned to five based solely on motivation and reward.
As team B sprawled out in the grass, still catching their breath and recovering, Shouta could hear his group yelling and snapping at each other. A few minutes later, team A came running to a halt in front of the others.
“How the hell did you expect us to win that?” Bakugo yelled, his quirk crackling in his hands. Shouta smirked and stood up.
“What do you mean, Bakugo?”
“We weren’t allowed to fly over things or climb on the buildings, we couldn’t go through certain obstacles and we had to go the long way!” Mineta whined, and the others chorused in agreement.
“We never said you couldn’t.”
Team A stopped. “Yes you did. You told us not to.” Kirishima spoke.
“No. Neither of us ever told you you weren’t allowed to do something. You could do whatever you saw fit. You chose not to do it when you heard us yelling.”
Someone on the ground spoke softly as team A began to yell. “Operant conditioning and the value of motivation.”
“Exactly.” Shouta said, moving to the front of the students. “Everyone sit. Thank you. Now, what you just learned was just summed up by Midoriya, but I’m willing to bet no one was listening. Say it again, please.”
“Operant conditioning and the value of motivation.” Midoriya said, his voice raising slightly. “It means that we were split into two test groups and given separate conditions to perform in. Your group yelled the whole time and you began to believe you were not allowed to do what you needed to, and your motivation decreased. Our group was rewarded and praised the whole time and we began to work harder and faster, motivating each other more.”
Team A looked back and forth between Midoriya and their teachers. “Is that true?” Hagakure asked, clinging to Ojiro while still trying to catch her breath.
“That is exactly what just happened. The first round, both groups had the same level of motivation. You both finished in fifteen minutes. No one was yelled at or encouraged. The second round, team A finished in twenty minutes after being yelled at and scolded, with less motivation. Team B finished in ten minutes after being encouraged and rewarded with more motivation. The third round, team A finished after twenty three minutes, yelled at each other the whole time, and failed to work together because they were no longer motivated to succeed. Team b finished in five minutes flat.” Shouta explained. He quickly looked around the faces of all of his students, some were too tired to care about their loss, others looked downright angry, and all of team B looked interested.
“Wait a damn minute.” Bakugo snapped, standing up and walking toward Shouta with a death glare. “You’re telling me that you conditioned me into acting a certain way just because of a psychological trap?”
“Yes. Can any of you think of anything else you have been conditioned into doing?” Bakugo growled as Shouta ignored him.
“I mean, taking care of ourselves or going to class would count, right?” Uraraka asked. Shouta nodded.
“What about how people talk? We just saw it happen!” Asui said, and again, Shouta nodded.
“How else can you be conditioned into doing something?”
“Food.” Bakugo said, the immediate realization taking over. “The damn nerd has been conditioning me into being nice to him ever since we were brats! With candy!” Suddenly all eyes were on Midoriya.
“Well, it obviously didn’t work, so I should stop now while I’m ahead.” Everyone except for Midoriya and Bakugo burst into laughter.
“That’s where the candy comes from? Every time we give him candy, he immediately calms down and becomes tolerable again!” Kaminari yelled, his laughter rocking his body backwards into Hitoshi a little harder than seemed comfortable based on the pained expression.
Bakugo stormed over to where Midoriya was sitting on the ground and pulled him to his feet. “You. You’ve been screwing my mind up since we were kids and I didn’t even know it.” The class watched as Midoriya reached into his pocket and pulled out a piece of candy, grabbing Bakugos’ hand and placing it directly into his palm. The silence was deafening. Suddenly, they began to laugh. Bakugo first, throwing his head back as he genuinely laughed at the hilarity of the situation. Then Midoriya joined him, the laughter carrying on to the rest of the class. Soon, everyone was laughing again.
“I’m sorry I played mind games with you Kacchan. I just wanted you to be my friend.”
“Honestly, I’m not even mad about it. I’m too tired for that. Don’t think I won’t get revenge on you for it though.”
Shouta smiled. Although the first year he had had these students had been a massive trainwreck, their second year was proving to be a great success. Friendships weren’t perfect, his students weren’t perfect, and honestly, he was glad they weren’t.
Although maybe he could condition everybody’s favorite problem duo into a better functioning friendship.
That would solve a lot of problems.