A Certain High School

A Certain High School (とある高校) is the term used to refer the yet-unnamed high school that the protagonist, Kamijou Touma is enrolled in. In the Toaru Majutsu no Index universe, it is the school in Academy City with the most named characters, next to Tokiwadai Middle School.

The school is located on a hill, and one needs to climb an inclination and a number of steps to reach its main entrance. It is assumed there is also an alternate way into the grounds, as staff members can park their vehicles inside the school grounds.

In December, the school was rendered unusable for the student body by the High Priest's attack on Touma and they were forced to move to Akikawa Mie's school until it could be repaired.

Appearance
The establishment looks like a typical Japanese-style school building. The school has a large main building, towering several stories and with several other buildings surrounding the main one. Like any standard Japanese school, they have lockers for the students, parking space for the staff, a faculty room, a cafeteria, and an auditorium, and the roofs are apparently accessible to any student in the school.

Around the school there are various areas of interest, such as open areas where students can congregate and consume their lunches; one is notable for being close to a small pond. The school also has a large field, probably used for sport-related events, as well as tennis courts.

Touma describes it in the novels as having two buildings, with the front being the new one, and at the back the old one. It is also described as being very ordinary, for a school in Academy City, having a flat campus and having the front and back buildings. There's also a semicircle roofed sports hall on the left, and a swimming pool on the right.

Uniforms
The summer male uniform appears to be a white dress shirt coupled with dark blue pants. The winter uniform includes the same dark pants, but the students wear a dark-colored jacket of the same shade. The female uniform is a sailor fuku which comes in both dark blue with white and white with dark blue (the former color is the main color, while the latter is used for stripes and borders) along with a dark skirt. Students seem to be able to make additions to their uniform if they wish, such as Tsuchimikado Motoharu wearing gold chains.

Index Arc
Touma attends remedial classes alongside his two friends, Aogami Pierce and Tsuchimikado Motoharu; they have a conversation on how Tsukuyomi Komoe - their teacher likes him and how Touma is lucky enough to spend time with her (because of punishment). Later during his remedial class, he thinks about Index and that he is aware that she has left it back in his apartment; however his daydreaming is cut short after Aogami Pierce snitches on him for looking at the girls playing tennis, which makes Komoe cry. This prompts several of his classmates to look disapprovingly at him.

Sisters Arc
The next day, Touma is one of his make-up classes, barely listening to Komoe's lectures. She reprimands him for it to which he responds that he wouldn't gain any power even if he listens. Both Aogami Pierce and Motoharu agree with him. However, Komoe says that they shouldn't give up. She cites on how Misaka Mikoto, the 3rd most powerful level 5 in Academy City was originally a level 1, however, due to hard work she was able to work her way-up to the ranks. Touma is rather surprised that she is the 3rd level 5 esper (as he had lost his memories). Komoe asks Touma if he knows Mikoto personally, to which he denies.

Kazakiri Hyouka Arc
The school is prominently featured during this arc, where the second semester starts and Touma is forced to leave Index at home to attend his first day of school since losing his memories. Here, he notes that he is quite nervous, as though he feels like a transfer student in a new school. Later on Index follows Touma, and is presumed by the class to be the new transfer student, but is dragged away by Tsukuyomi Komoe where it is later revealed that Himegami Aisa is the new transfer student. Index after wandering around she meets Kazakiri Hyouka in a cafeteria, and they become fast friends. Hyouka is later introduced to Touma, and later agrees to go to the underground mall with him and Index.

While Touma was out with Index and Kazakiri, Himegami and Komoe have lunch together where the brain storm the truth of the mysterious Kanzakiri using the data Komoe was compiling for a friend. Though they are not able to get a signal through until after Sherry Cromwell's attack had already started. They then give him the hypothesis on what she truly is and her relationship to the Imaginary Number District–Five Elements Institution and how she came to be.

Daihasei Festival Arc
The school is later used as a battlefield against an opposing team in the Daihasei Sports Festival, where after Komoe was belittled by an opposing teacher, gave Touma and his schoolmates the spirit to defeat the opposing school, giving them a win.

Academy City Invasion Arc
As it was the final day of September, every school in Academy City had only morning classes. This was simply because the schools switched to using winter uniforms the following day. The actual measurements and orders were carried out at around the time of the Daihaseisai, so the only thing left was for the students to pick up their new winter uniforms. Even so, the congestion was on a great enough scale to require special treatment. Having only morning classes was also customarily a means of giving the students a time to wear their winter uniforms and “break them in”. For those who the winter uniform they had purchased when entering the school still fit fine were spared having to deal with the busy stores on that day.

Touma, on the other hand, gets his daily share of misfortune at school. He gets punched in the face by friends Tsuchimikado and Aogami, who felt mocked by Touma's wishes to meet someone, and he has to watch the two arguing about their lack of contact with girls (which arose from Aogami's complaints of a stiff shoulder). Touma then gets an idea: "How about talking to the girl who is addicted to shopping on the TV for opinions?" However, that didn't work well for the three. Upon their charge towards Fukiyose, Tsuchimikado and Aogami received a hard fist on their stomachs while Touma is hit by Fukiyose's forehead, knocking the three at the same time. Komoe then comes in to start chemistry class, only to be frightened by the bodies of three unfortunate guys. Accelerator finally reaches the meeting place with Last Order and Yoshikawa Kikyou. There, she introduces Accelerator to Yomikawa Aiho and Tsukuyomi Komoe. Accelerator then expresses his shock at Komoe's petite figure, then assumes that she is part of an experiment that involves stopping cellular aging. Komoe protests at his idea of her as a guinea pig, and soon, Aiho invites them to her car to take them to her apartment. There, Accelerator wants to confirm if Aiho is determined to take them into custody, considering his contact with the dark side of Academy City. Aiho proudly tells him that her job will keep her safe at best. Accelerator continues to point out the risks of taking him in, but Aiho smiles and instead, pertains what he has been blurting out as his declaration that he will protect them, much to the Level 5's annoyance.

Skill-Out Uprising
A few days later, things appear to have returned to normal after the events of September 30. At A Certain High School, it is lunchtime. After the others have run to the cafeteria, Touma brings out his own lunch. Himegami Aisa accompanies him with her own boxed lunch, and the blunt girl with the hime-cut proceeds to comment on Touma's preparation of his boxed lunch.

Meanwhile, as Tsukuyomi Komoe walks with colleague Yomikawa Aiho just down the hall. Aiho comments on Komoe opening her apartment room for another "run-away kid", and Komoe tells in response that things got lonely after Aisa left her apartment room for the school dormitory, and that now is fine since Musujime Awaki is living with her. Likewise, Aiho remembers Accelerator leaving her house. Soon, Komoe and Aiho arrive in front of the class that Komoe usually teaches and the pink-haired teacher is shocked by the chaos inside the classroom. As Komoe assesses the situation inside, Aiho remarks that she is somewhat jealous of Komoe's class, who is able to enjoy things without any worries.

Document of Constantine Arc
Touma, Motoharu, Aogami and Seiri were sent to the teachers lounge after a scuffle was discovered by Oyafune Suama, a teacher at the school. The issue was about the three boys talking about which color would suit the bunny girl better (black, white or red), but Seiri with her own brand of justice, chokes Motoharu, kicks Aogami and headbutts Touma After summoning Saigo to put them in their place, she orders the four to pick the weeds off the school grounds. . As punishment Suama orders the four to pick the weeds off the school grounds however Motoharu and Aogami ditch leaving Touma and Seiri to work together. Touma asks if Seiri is preparing for her exams despite having to be cancelled because of the chaos that's happening in Academy City and across the globe. She remarks that she won't let him see her notes much to his disappointment. They end up getting distracted and start playing fork ball, and while getting ready for a pitch her panties become visible thanks to Touma's warning and bad timing. They continue to play fork ball until the two accidentally hit Suama who forgot about them and was coming to check on them. When they accidentally hit Suama and Touma goes to apologize but the angry Suama tries to strike Touma but she misses and he then asks if he can go home but she whips something at him prompting him to run away. and the time getting late and Touma goes to apologize but, finds her in the middle of changing out of her dirt covered clothes. The now even angry Suama tries to strike Touma and she misses and he then asks if he can go home in reply she throws more math instruments at him prompting him to run away.

Acqua of the Back Arc
Touma and his friends were late for lunch because of a stupid comment he made. In the faculty room as Komoe's class begins to starve due to lack of lunch. Here, as Touma pleads his case to open the culinary classroom, the teachers are eating their lunches which just has Touma leaving with in irritation. As a class they lamenting the fact they had nothing to eat, when Fukiyose Seiri comes up with the plan for all of them to run out side at the same time and split up, Motoharu pulled out a scrap piece of printing paper and immediately drew a detailed map of the school. The class designates a team of Touma, Motoharu, Aogami and Seiri as the four to undertake the task at hand, sneak out, they are spotted by the gorilla-like teacher.

British Royal Family Arc
As the midterm exams had been cancelled due to various circumstances, the students must have felt they had more spare effort to put into the Ichihanaransai festival. Touma's class had formed small groups around the classroom and seemed to be in a fairly festive mood. Two primary examples were Aogami Pierce and Tsuchimikado Motoharu who were next to Kamijou, arguing over waitresses or maids for their cafe. As perusal this conversation is ended by a head-butting from Seiri.

Eve of the Festival
As Touma awakens in a station, not knowing how he got there and back in Academy City. While he ponders what had happened in Baggage City, and regarding Fiamma of the Right and Ollerus. He then hears footsteps, and as he turns around, he discovers that it is of his classmate Seiri. Here, she is carrying supplies for the Ichihanaransai. After Touma had the nerve to ask what she is doing at the station where he is left off, Seiri attacks him with one of her bags, reminding him that he is the one who has the skipped the preparations for the festival. Seiri later uses the duct tape in her bag to subdue Touma and carry him back to school telling him that they are shorthanded, much to his remonstrations as Touma wants to see Index in their dorm however, she ignores him. She is apparently uncaring of Touma's well-being as she dragged him in the streets and later shoves him into their classroom, declaring him as a fugitive, before moving to her own station. Here, Tsukuyomi Komoe tells Touma that his absences has reached the point in which homework and supplementary lessons can't cover it. She asks Touma if there are any problems he is facing that may be the reason for his absences, and later asks why he is so beat up. Although, Touma could only give half-hearted replies. He is later reunited with Tsuchimikado Motoharu and Aogami Pierce, and predictably get into an argument regarding perverted cultural festival events, necessitating for Seiri to intervene. With everything settling down, Touma is later told by Seiri that she'll need him to stay over tonight, much to Touma's dismay as he still wants to go back to his dormitory and see Index. Seiri then instructs him to buy some food for them, and gives him money for it.

With his cart, Touma tries to do what Seiri told him to do, that is, until he notices Ollerus. He notes to Touma on how it took so long for Touma to sense him, noting that he lost a bet with Fiamma of the Right, and says that he wants to talk about the Imagine Breaker to him, but Touma ignores him much to his surprise, as he still intends to deliver the food that Seiri has tasked him to do.

Later Mikoto arrives at the school to see the true essence of a school was better seen during the preparatory period of the festival. She is quickly spotted by Komoe who recognizes her uniform while Mikoto believes that she is an elementary schooler visiting the school as well. After making an off hand comment on the laxness of the school, they over hear Seiri yelling about Touma running off again and arrest after his scuffle with Thor. After releasing Fräulein Kreutune Touma and Thor headed to a certain school where, after hearing Komoe and Seiri talking about his disappearance again Touma quickly blames Thor before going inside. They quickly head to the computer lab where they implemented their plan to trap for both GREMLIN and Ollerus’s group. By having Thor transform into Marian Slingeneyer to make a fake Anti-Skill bulletin.

During the Festival
8 AM during the start of the festival, Mikoto decides to come back to Touma's school. When she approaches the main entrance of the school for the trial enrollment, she bumps into Shokuhou Misaki, who was using her ability to make the crowd chase after Mikoto. She then constantly cursed Misaki for always teasing her but soon stopped as she started to wonder what she was doing there in the first place. However, she quickly cast away that thought as the crowd caught up with her again.

Magic God Othinus Arc
The school is present in both the Beta World and Omega World that Magic God Othinus has created to break Touma's spirit. In the Beta World, it is where Touma first sees "Kamijou Touma" a person who is living his life, and where Othinus tests who Touma is by making him question his identity. In the Omega World, it is where Othinus meets Touma again after breaking free from his despair. The school apparently serves a symbolic purpose for Touma. Here, Touma does battle with Othinus, dying, and being resurrected countless times by her due to her hesitations. The school along with the rest of the world is later destroyed as Touma's countless battles with her continue on.

Magic God Invasion Arc
As the Anti-Crime Orientation takes place in School District 7, the school is forced to participate with Touma roleplaying as a criminal. He runs away from Fukiyose Seiri and later Misaka Mikoto by going through the windows. Mikoto uses her Railgun on Touma after sighting him outside wearing the "criminal attire", likely damaging the school building in the process. After escaping, Touma comes into one of Kumokawa Seria's hideouts, and as she is a "hostage" character for the orientation she acts out as being caught by Touma. Seria later helps Touma try to escape the orientation but is sidelined, much to his pleasure by a love letter in his locker asking Touma to come to the roof of the school building, much to Seria and Mikoto's chagrin. The letter is later found out to be from the magic god High Priest. At the roof the High Priest tries to convince Touma to become the mediator of the magic gods in the world, essentially handling him control over them. After Touma refuses his offer, the High Priest attacks using a dirt hand and slams it into the school. The building is decimated, but thanks to Motoharu playing the role of "criminal" for the roleplay, he is chased by the "police" characters to the other side of the building away from the damage, giving some relief to Touma that not everyone in the school is dead.

Salome Arc
On December 4th, with the school building unusable due to the damage caused by the High Priest, the school's students and staff moved to another school, borrowing their unused facilities to continue lessons.

Element Arc
The school remained unusable during the coming days, with repair work suspended together with normal activities in the city following the arrival of an abnormal heatwave and the Elements. At one point during the heatwave, Mikoto briefly visited the school under the impression that Touma was still there.

Level Upper Arc
The school is featured prominently in the Toaru Kagaku no Railgun anime, where Level Upper users were required to attend a special class. Here, a melancholic Saten Ruiko and her friends spend the day relearning about Personal Reality, and discovers the meaning of surpassing one's own limitations. Komoe and Yomikawa Aiho appear during this episode and helps the Level Upper users realize that they can gain their own Personal Reality- their own ability- themselves if they try. By the end of the day, the Level Upper users have an scan on their abilities, and though they remain Level 0, Ruiko and her friends discover that a few of their attributes increased. Ruiko herself notes that she will do her best after looking at her own results.

Toaru Majutsu no Index: Love Letter Competition
Kumokawa Seria arrives in their classroom looking for Touma, and finding out that he isn't here, asks Seiri, the girl with black hair, huge breasts, and large forehead, for aid. Seiri wastes no time showing her distaste for her senpai, calling her a noisy idiot. Despite that, she is forced to approach her to answer her summons. She points out that her hairstyle was the same since she was five and says that she shouldn't judge people based on her standards. But Seria counters by saying that her hair was the same as when she was five as well, forcing Seiri to point that out. Seria, however, contends that she is her senpai, thus Seiri is younger than her by a year. With that they see face to face and breast to breast, garnering the attention of Motoharu, Aogami, and Aisa. As they bicker on using innuendos regarding her breast, Seiri demands to know why an experienced senpai like her would come into a class full of brats. With that, Seria brushes an envelope on Seiri's forehead, forcing her to pull away from her stare down with Seria due to the friction, telling her that she needs more training. Seiri immediately recognizes that it is a love letter, and almost misunderstands Seria's intentions until she is tasked by Seria to pass it to Touma for her. Seiri is shocked. Seria tells Seiri that it should be easy to pass that letter to him and leaves. Seiri later realizes too late what she has gotten herself into. Fukiyose Seiri thinking that it would be a bit of hassle, decides to give Komoe the "love letter" Kumokawa Seria gave for Kamijou Touma instead. after giving it with Komoe she then runs off, leaving her no choice in what to do. Yomikawa then comes over to tease Komoe making her even more flustered while also morning that she has to miss out no her black stout.

Toaru Majutsu no Index Movie: Miracle of Endymion
Touma deals with the inane talk of his friends (mostly concerning the announcement of Meigo Arisa), and the prodding of his classmates of his night life. Seiri then appears, right after Aisa overreacts on overhearing that Touma did not sleep and that is pillow was taken, apparently confused. Komoe comes soon to teach Touma a lesson, specifically, supplementary lessons for him.

Year 1 Class 7
Year 1 Class 7 is the most prominent class in this school featured in the series, being that it is Touma's homeroom. The homeroom teacher is Tsukuyomi Komoe the chemistry teacher, who is beloved by the students of her class. It is stated that the room lacks an air-conditioning system, though it is unknown if it applies to all classrooms in the high school. From Volume 6 onwards, the entire class knows Index and takes kindly to her.
 * Kamijou Touma
 * Tsuchimikado Motoharu
 * Aogami Pierce
 * Himegami Aisa
 * Fukiyose Seiri
 * Headband girl
 * Spiky-haired glasses girl

Other students

 * Kumokawa Seria

List of notable staff

 * Tsukuyomi Komoe
 * Yomikawa Aiho
 * Oyafune Suama
 * Saigo

Trivia

 * It was implied during the beginning of Volume 12 that Accelerator was going to transfer into Yomikawa Aiho's class. However, due to the 0930 Incident and his initiation into GROUP, Accelerator transferred to Nagatenjouki Academy instead.
 * It's implied in Shinyaku Toaru Majutsu no Index Light Novel Volume 05 that Misaka Mikoto wishes take the entrance exam for the school.