Welcome to Demon School! Iruma-Kun is primarily an isekai anime series, but it also has strong "school life" themes like My Hero Academia or Horimiya, meaning protagonist Iruma Suzuki is a student in another world. He's a first-year at Babyls, an all-demon school in the Netherworld.
Iruma Suzuki relies mostly on luck and his friends to make it through school since he has no demon powers and limited academic skills. He's doing his best, but Iruma often struggles with studying and needs Opera to tutor him. Iruma is no honor roll student, so he ought to get tutoring from a handful of other, smarter anime students who can get an A+ every time.
10 Momo Yaoyorozu Can Ace Any Test
My Hero Academia
My Hero Academia has a major school theme, hence the title, and U.A. students like Izuku Midoriya must study more than quirk techniques. Every U.A. student must study hard and pass written tests, and Class 1-A's students are all over the place. Mina Ashido, for example, merely laughs off her terrible grades while Denki panics about his abysmal test scores.
Momo Yaoyorozu, meanwhile, is Class 1-A's smartest student and likely U.A.'s smartest student overall. She breezed her way to the top of Class 1-A's rankings, and Momo also generously tutored her classmates without asking for anything in return.
9 Senku Ishigami Was Far Ahead Of His Classmates
Dr. Stone
Senku spent most of Dr. Stone in a post-apocalyptic world dominated by a new Stone Age, so he was rarely seen in his 21st-century high school. Still, Senku Ishigami is a brilliant scientist who can memorize or calculate almost anything, which is highly impressive.
Anime fans can easily infer that Senku was his school's top student, and he likely knew more science than his actual science teacher did. He could even outperform grad students in 21st-century Japan, but in the new Stone Age, he won't ever get that chance; he has new challenges to face.
8 Demetrius Desmond Is An Imperial Scholar
Spy x Family
Spy x Family features Eden Academy, Ostania's most elite place of learning. Usually, it's the sons and daughters of Ostanian's elite who study there, with Anya Forger being an exception. Anya thinks she has her hands full with the tsundere Damian Desmond, but then there's Damian's much older brother.
Demetrius Desmond has yet to appear directly, but Spy x Family fans do know he's an Imperial Scholar and an ace student. Brilliant students like Demetrius are Ostania's future, and no doubt Donovan is very proud of him, while Loid Forger is intimidated by the very idea of him.
7 Shoko Komi Always Gets Good Grades
Komi Can't Communicate
Komi Can't Communicate stars the lovable dandere Shoko Komi, who is more focused on making 100 friends than acing every test to get into a good college. Shoko may not be Itan high school's #1 student, but she still ranks high based on the test scores anime fans have seen.
Shoko scores above average in all subjects, sometimes scoring far above average, in fact. Aside from her shyness, Shoko could be a great tutor for her classmates, with Hitohito Tadano getting average scores and Najimi Osana scoring well below average.
6 Miyuki Shirogane Is A Student's Student
Kaguya-Sama: Love Is War
In Kaguya-Sama: Love Is War, Kaguya Shinomiya grew up fabulously wealthy, so she had access to private tutors. That, and her natural intelligence, makes her Shuchiin Academy's #2 student. However, not even she can match Miyuki Shirogane's tireless work ethic and discipline.
Miyuki tops the school's charts with his outstanding test scores, and he has studying down to a science. He has little choice since his family lives in poverty and he doesn't come from society's elite, like Kaguya, Chika, and Yu do. Miyuki trained himself to be the perfect student, with no expensive tutors needed.
5 Futaro Uesugi Tutored The Nakano Sisters
The Quintessential Quintuplets
Futaro Uesugi grew up in a household of modest means in The Quintessential Quintuplets, so he made up for it with his excellent study habits. Futaro believes that academic excellence is the key to his future, and now he can share what he knows with the five Nakano sisters.
Futaro was trusted to tutor the quintuplets and help them raise their horrible grades, a new challenge Futaro didn't feel ready for at first. Futaro learned over time to get along with the Nakanos and get through to them, and they learned plenty from him in return.
4 Light Yagami Breezed His Way Through High School
Death Note
Death Note protagonist Light Yagami is best known for being an antihero and a supervillain in the making, yet he was introduced not as a criminal, but a high school third-year student. Light was bored in class, not because he hated school, but because it didn't challenge him.
Light breezed his way through school, then got into a good college with perfect entrance exam scores. Even then, in Light's own words, there was no one at To-Oh on his level, so he had no one to talk to. The sole exception was L, who also got in with perfect scores and could challenge Kira properly.
3 Misaki Ayuzawa Is A Disciplined Student
Maid-Sama!
Maid-Sama! is a whirlwind romance anime whose protagonist, Misaki Ayuzawa, is determined to do it all. Misaki runs the student council at Seika high school, and she is also an active disciplinarian. Misaki also works part-time as a maid to support her family.
Misaki also finds the time and energy to study hard and get good grades both to set an example at school and to maximize her options for college and employment later. Now and then, Misaki might wear herself too thin, but then she'll bounce back and dive right back in.
2 Chisa Kotegawa Takes College Seriously
Grand Blue Dreaming
Grand Blue Dreaming focuses mostly on comedy and SCUBA diving, but the main characters may also appear in class, where they tend to crash and burn. Protagonist Iori Kitahara tends to goof off and struggles at his new seaside college, but his tsundere cousin, Chisa Kotegawa, is a fine student.
Chisa is a serious, focused young woman who takes diving seriously, and graduating college is another major priority of hers. In the manga, for example, she got an impressive score on a German test that everyone else found incredibly difficult, and Chisa thought nothing of it.
1 Shinya Yukimura Is A Grad Student Superstar
Science Fell In Love, So I Tried To Prove It
Science Fell in Love stars a handful of college grad students at Saitama University, all studying hard sciences. Arguably, the smartest and most disciplined of them is the kuudere Shinya Yukimura, the handsome young man whom Ayame Himuro couldn't help falling for.
Shinya has loved science since his boyhood, and it's evident he's one of Saitama University's best students. When he graduates, Shinya could find work in any lab he wants, and the same is true of his fellow students, Ayame and Ena, for that matter.