0. Short answer: Sukuna's weak spot isn't grades, it's "why should I fit in with you?"
This is a just-for-fun Jujutsu Kaisen school AU, not canon. Put Ryomen Sukuna in a regular school and the trouble won't be math, English, or science. The trouble is that he'd barely feel any need to bend himself to what the group wants.
The official Jujutsu Kaisen anime site calls Sukuna the King of Curses. He lived more than 1,000 years ago, and even the sorcerers of the golden age of jujutsu, giving everything they had, lost to him.[1] Late in the manga he keeps fighting the strongest sorcerers of today, one after another.[2][3] None of that proves he'd get 100 on a math test. Still, "Sukuna can't keep up because class is too hard" makes no sense, even as a school AU.
Here's the report card I'd guess he gets:
| Subject | My guess | In a nutshell |
|---|---|---|
| Academics | Close to 5 | Learns fast. The problem is whether he cares |
| Physical ability | 5+ | The gym teacher gives up on grading |
| Ethics class | Written test 5 / real life 0 | Knows the right answer, just doesn't use it |
| Choir | Skill unknown / teamwork 1 | Not that he can't sing, he won't blend in |
| Group projects | 0–1 | Finishes alone and makes the "group" pointless |
| Attendance | 2 | Shows up only on days with an interesting challenge |
So Sukuna's worst subject isn't in any textbook. It's working together.
1. He's not bad at studying, he just has no reason to obey
School teaches you stuff, but it's also one big sync machine. Show up at a set time. Sit in your assigned seat. Start when the teacher says go. Split up the jobs. Even if you finish first, you wait for everyone else.
That's probably where Sukuna and school collide.
It's not "can he do it?" Every single time the question is "why would I follow this rule?"
Tell him "it's the school rule" and he shrugs, because he didn't make it. Tell him "everyone else follows it" and that's even weaker. Being in the majority doesn't seem like something that would convince him.
So he fails in the opposite way from a normal kid.
It's not "can't do it, so can't take part." It's "can do it, but sees no point in taking part."
For a teacher, that's much harder to deal with.
2. He'd probably ace plenty of subjects, and still wreck the report card
Math and science look like a good fit. That's my guess, not canon. But in fights he reads the situation, studies the other side's abilities, and combines several tricks, and that style seems to suit abstract, rule-based problems.
Language arts doesn't look like a weak spot either. His words cut as precisely as his attacks. Classical literature is the funniest: someone from over 1,000 years ago sits in the classroom, so it's basically a historical source attending the lecture. Of course, living back then doesn't mean he'd automatically ace a modern test on classical grammar. Keep the joke and the actual skill separate.
PE is no problem for his body. The trouble is rules and syncing up. A 50-meter sprint is fine. Lining up, shouting commands, and doing partner drills? That's where it gets weird.
Home ec and shop class work the same way: great at the hands-on part, group work blown to pieces. Say four people are supposed to split the cooking jobs and Sukuna does all four himself. The meal gets made and the lesson plan dies.
Social studies is fun when it's history. The teacher will want to grill a living witness from 1,000 years back. But once civics covers majority vote, group decisions, and rights and duties, the class turns into a talk show.
And the two real problem subjects are ethics and music.
3. Ethics: not "he doesn't know the right answer," but "he knows it and says no thanks"
It's tempting to give Sukuna a 0 in ethics. The funny part is that on the written test alone, he'd probably score high.
Psychologists separate working out what someone else thinks and feels from actually reacting to those feelings yourself. That's the split between cognitive empathy and emotional empathy.[7] I'm not diagnosing Sukuna with this study. It just helps explain that "I can read how you feel" and "I want to help you" are different skills.
In the story, Sukuna keeps reading people's intentions, weak points, desires, and fears. He isn't a simple "he does bad things because he can't understand other people" kind of character.
Picture the class:
Teacher: "A friend is feeling down. What would make them feel better?" Sukuna: "Hear them out, and help if they want it." Teacher: "Correct. So will you do that?" Sukuna: "Why would I?"
Understanding: 100. Actually doing it: 0.
Ethics teachers would lose sleep over this. If a kid doesn't get the answer, you can teach it. If he gets it perfectly and asks "why should that be my goal?", class suddenly turns into philosophy.
4. Choir: it's not about singing, it's about syncing up
Nothing official says how well Sukuna sings. What's funny is how choir works.
A choir isn't won by the best singer blasting at full volume. You have to listen to the people around you and match their volume, timing, tempo, vowels, and breathing.
Teacher: "Listen to the others and bring your volume down a bit." Sukuna: "Why do I have to match them?"
And that's game over.
Say school-AU Sukuna learns the melody and harmony after one listen. That's still just our imagination. Even then, skill 100 with zero willingness to cooperate still isn't a choir.
The second he sings flat out, it's no longer a class choir. It's
"Ryomen Sukuna feat. Class 2-3."
When the conductor says "tone it down a little," it stops being a music problem and becomes a question of who's in charge.
5. Group activities: he can do all of them and ruin all of them
Lining up: Sukuna has no reason to keep his distance from the person in front of him.
Long jump rope: he can jump just fine, but he hates fitting himself to the timing of 30 people. He'd end up saying "make the rope match me."
Three-legged race: if his partner is slow, he might just pick the partner up and run. Fastest time, instant disqualification. He wins the race and loses the lesson.
Cooking class: finishes four people's work alone. Food done, teamwork dead.
School festival: "Let's all talk it over and decide together" is the biggest landmine. For Sukuna it ends with "we're doing my idea."
So his school fit comes down to a neat formula:
Teamwork as equals ×, a temporary deal where interests line up ○, teamwork where he's in charge ◎
It's not that he can't do anything with other people. What he's worst at is bringing himself down to the group's level as one equal member.
6. Why all the usual discipline cards do 0 damage
Psychology has an idea called reactance: when people feel their freedom is being taken away, they push back. A 2025 meta-analysis found that wording that strongly limits freedom, like "you must" or "you have to," tends to cause more reactance than softer wording that leaves a choice.[4]
Nobody has ever measured Sukuna on a reactance scale, of course. But as a way to explain this school AU, it fits almost too well.
"It's the school rule." "Everyone does it." "Listen to your teacher."
All three cards do 0 damage.
Self-determination theory, meanwhile, says motivation depends on autonomy (choosing for yourself), competence (feeling capable), and relatedness (feeling connected). A 2024 systematic review and meta-analysis of education studies covered 36 studies and 11,792 people, and reported that methods supporting autonomy and competence worked.[5]
For Sukuna, the bait isn't relatedness. It's autonomy plus competence.
"Do it for the class" won't move him. "This is a hard task you can't solve with raw strength alone" might make him look up.
7. The crayfish-fishing trick: don't ask nicely, dangle "bet you can't do this"
That brings us to the crayfish-fishing trick.
You don't drag Sukuna along. You hang a hard, interesting challenge in front of him like bait and let him bite on his own.
Teacher: "You don't have to join choir. Though matching the breathing and volume of 30 people with zero slip-ups is harder than singing solo." Sukuna: "..."
🎣 Got a bite.
Teacher: "You can skip the long jump rope too. Being fast on your own won't get you through it." Sukuna: "Who are you calling not good enough?"
🎣 Crayfish number two.
Add "Gojo-sensei could do it" and he might take the whole fishing rod, not just the bait.
An experiment also found that people's intrinsic motivation tends to go up when the challenge fits their skill level.[6] That doesn't prove goading Sukuna works. It just backs the basic idea that a good challenge can motivate better than a boring duty.
The point is that the crayfish trick isn't about insulting him.
Leave a choice instead of giving orders, present it as a skill to master instead of a boring duty, and give him room to jump in on his own.
I'm not saying you should taunt or humiliate real students. What education research supports is explaining things and offering choices that respect a student's autonomy, not teachers teasing kids.
8. Gone after five minutes on day one, but he shows up on test day and gets a perfect score
Imagine the first morning.
8:30, Teacher: "Please take your seat." Sukuna: "Why?"
8:31, Teacher: "It's a school rule." Sukuna: "I never agreed to it."
8:32, Teacher: "Everyone follows it." Sukuna: "So?"
8:33, Teacher: "It'll hurt your school record." Sukuna: "And?"
8:35, he goes home.
The real problem is that he doesn't seem like he'd fall behind in his studies either. If he reads the textbook at home, shows up only for exams, and scores almost perfectly, the school is even more stuck.
Mon ○ Tue × Wed × Thu ○ (a hard lab today) Fri ×
A student who only spawns for events.
It's less "school makes it impossible for him to do anything" and more "he doesn't log in when there's no interesting event."
By the end of the week, the homeroom teacher learns that "come every day" won't work. The school has to look like a place where something worth seeing happens every day.
Difficulty to manage: special grade.
9. The final report card: academics 5, teamwork 0, teacher stress "special grade"
Here's his final report card:
Academics: 5 Physical ability: 5 Following instructions: 5 Understanding the model answer in ethics: 5 Ethics in real life: 0 Teamwork: 0 Attendance: 2 Joining tasks he finds interesting: SSS Homeroom teacher's exhaustion: Special Grade
It would be a bit off to boil this down to "he's bad at ethics," "bad at music," or "bad at PE."
Ethics: he understands the values fine, he just doesn't take them on. Choir: he can sing, he just has no reason to sync up. Group activities: he can do them, he just has no motivation to lower himself to the group's level.
So his biggest weak spot isn't a subject. It's the assumptions school treats as obvious.
10. Conclusion: Sukuna's toughest enemy might be class activities, not Gojo
What the school wants is simple:
"Come at the same time every morning, and do the same task, on the same signal, together with everyone."
What Sukuna wants is simple too:
"Give me something worth doing."
Those two demands are scary mismatched.
If you really wanted Sukuna to keep going to school, a boss rush every day would probably work better than piling on more rules. Choir, jump rope, and group projects won't catch him if you say "let's cooperate." Call them "hard tasks you can't clear on strength alone" and he might reach out his claws like a crayfish.
And the final boss of school life isn't a test or an entrance exam.
It's this sentence:
"Today we won't pick a leader. Let's all talk it over and decide together."
Sukuna's toughest enemy is probably class activities.
- Official TV Anime Jujutsu Kaisen — Character: Ryomen Sukuna: https://jujutsukaisen.jp/character/index_1st.php
- Shueisha, Jujutsu Kaisen Vol. 27: https://www.shueisha.co.jp/books/items/contents.html?jdcn=08X10000000048680300
- Shueisha, Jujutsu Kaisen Vol. 30: https://www.shueisha.co.jp/books/items/contents.html?isbn=978-4-08-884378-0&mode=1
- Human Communication Research, “Message effects on psychological reactance: meta-analyses”: https://academic.oup.com/hcr/article/52/1/38/8178818
- Wang et al. (2024), “A systematic review and meta-analysis of self-determination-theory-based interventions in the education context”: https://selfdeterminationtheory.org/wp-content/uploads/2024/06/2024_WangWangEtAl_MetaEdu.pdf
- Meng et al. (2017), “Inverted U-Shaped Curvilinear Relationship between Challenge and One's Intrinsic Motivation”: https://pmc.ncbi.nlm.nih.gov/articles/PMC5368271/
- Campos et al. (2023), “Dissociating cognitive and affective empathy across psychopathy dimensions”: https://pmc.ncbi.nlm.nih.gov/articles/PMC10345207/
