"One such setting is the "Nine Schools Battles", officially called The National Magic High School Good Will Magic Competition. Every year, the best Magic High School students gather together, unfolding a story of frustration and glory by putting their young pride on the line."

(Adaption of Light Novel v03-v04)

Natsuyasumi-hen follows a variety of characters over their summer break between the Nine School Competition Arc and the Yokohama Disturbance Arc.

Manga adaptation of the 6th arc of the Mahouka Koukou no Rettousei series.

(Adaption of Light Novel v09-v11)

At the Yotsuba New Year's gathering, Miyuki was names as the successor whilst Tatsuya was named her fiancé. Tatsuya and Miyuki's non-sibling relationship and engagement are now public knowledge. Among the shocked students the most shocked are those that knew the siblings.
Meanwhile, the Ten Master Clans selection meeting, followed by magicians all over the world, is due to take place at a hotel in Hokone.

Adaptation of the original novel's volumes 17-19.

"Three years ago, he had the same posture.
Three years ago, he had stood behind Miyuki.
Yes.... Compared to three years ago, it had changed."

Set three years prior to the present time, Tsuioku Hen tells the events that would change Miyuki's world drastically, as well as the events that led Tatsuya to become what he is now.

(Adaption of Light Novel v08)

The Thesis Competition, an event with as much importance as the Nine School competition, this competition has the particularity to have its competitor brain compete to see which one has more mastery on magic theory. However, things may not go smoothly ... And "disturbance" may unfold...

(Adaption of Light Novel v06-v07)

In December, Miyuki receives an invitation for the Yotsuba's new year's family gathering. However, unlike previous years, they specially added "Everyone must attend" on the invitation. Miyuki understands that "the time has come" — it is time to decide the next head for the Yotsuba Clan.
— If she is elected, her brother will be free.
— If she becomes the next head, she will be forced to marry someone else.
Miyuki's heart is a mess.
The truth of the Brother and Sister relationship is finally unveiled!? Yotsuba Keishou-hen begins!

Adaptation of the original novel's volume 16.

A side story of Mahouka Koukou no Rettousei that focuses on Shiba Tatsuya's younger sister's viewpoint and experiences of the events taking place in the main story.

From Yen Press:

Kidnapped and stuffed into a trunk by an unknown assailant, teenager Kazumi bursts forth from the confines of the case to discover that she has been stripped not only of her clothes, but also of the memories of her life before the kidnapping. When she is recovered by a pair of schoolgirls, she doesn’t recognize them as her best friends and roommates, Umika and Kaoru. As Kazumi tries to settle back into her normal life, she quickly realizes that her former “normal” was anything but!

N/A

From Nakama: Without worries about girls or money, halfheartedly living Nishizaki meets the love of his life on campus. A lover who bites his lips when happy... Araya is always troublesome, gloomy, and without desire. Thinking of him, Nishizaki’s teeth always hurt...

The story revolves around Suzunoki Hatsune, a normal high school girl... or so she strongly wishes, because she has no desire to succeed her stepfather as the strongest onmyouji in modern Japan. Still, she has the ability to see spirits, and as luck would have it, her emerging abilities are pointing her to a terrifying truth behind the deaths of her parents... and her stepfather may be involved!?

From the manga habit:

Rio is a 14-year-old boy with no particular special traits, except his burning love for books. He's awkward and considered odd at best by his peers. Rio also has a twin brother, Mao. Although they look alike, they couldn't be more different. Mao is good at everything, is popular, and has future plans to have a big, happy family. Despite their differences, the brothers are close.

One day, when Rio attempts to retrieve a cat that wandered into the street, he is hit by a car right in front of his brother's eyes. Everything fades to black. In the darkness, a voice offers a choice: to live or to die. Fading rapidly, Rio gives the obvious answer: to live!

Rio awakens in a world filled with foreigners and strange animals he's never seen before. That's not the only odd thing–Rio now has the form of a black cat! He quickly learns cats are revered in this world because of their special role as familiars of wizards.

The war that raged between the Church and the Witches for five centuries finally ended in peace but a few short years ago. However, nestled in the shadowy places of the world, the embers of that age old conflict still smoulder.

Attending the Royal Academy of Magic of the Kingdom of Wenias is a struggling student named Sable, who has no memories of his time before being enrolled. At the command of Headmaster Albus, he left the Kingdom to travel to the southern reaches of the continent, where anti-magic insurgents are still a force to be reckoned with, as part of a special training regimen. Accompanying him are a party of individuals strong in both ability and personality; there's the one known as the Witch of the Dawn, Roux Cristasse, who seeks the forbidden knowledge of primeval magic in the 'Grimoire of Zero', the genius girl Holtz, as well as the school's sole beast, Kudd.

Just what truth shall they uncover in their journey to the south…?

From Storm in Heaven:Magicians, people with magical powers that have caused their kind to be hated and feared throughout the centuries. This manga contains their tales -- of magic for both good and evil, the struggle to fit into society, and a dark past that haunts them both.The series includes:1) Romanesque Variee2) Mystic Variee3) Classical Variee4) Sweet Variee5) Silouette Variee6) Crescent Variee7) Secret Variee8) Fantastic Variee9) Nostalgic Variee

From Terrad:
Sae and her friends from school make the "Magic-Users Club", where they try to learn magic (usually ending in some horrible/funny mess-up).

Hardworking level one magician Konoha is apprenticed to lazy Knight Protector Saionji Ikumaru. They both work to keep the ether world sealed away from their own but sometimes the seal doesn't work. Dragons, demons, and now Ishtar, the goddess of Venus. Will Ishtar help Konoha win her master's affections? Or will she take him for herself?

From MangaHelpers:
Mai has been helping out her childhood friend, Kunimitsu, every morning with soccer practice ever since they were little. After years of practice, Kunimitsu has been MVP 2 years in a row at the middle school nationals. One day, Reika - one of Kunimitsu's admirers - witnesses the two childhood friends practicing, and is shocked by Mai's ability to keep up. Determined to prove herself to Kunimitsu, Reika challenges Mai to a soccer challenge. Caught between her childhood crush and new competition, will Mai be able to hold her composure? With a tendency to get too nervous or fantasize about Kunimitsu, Mai has a hard time playing soccer outside of practice. Can she stop her lewd fantasies long enough to beat Reika?

18-year-old Mai Sugimoto is a college student starting this year. She was looking forward to the "college life," but she ends up living with two women because of a realtor's mistake. Furthermore, they are all 18-years-old and share the exact same name, Mai Suigimoto. Hence a life story of three Mai(s) full of fun and erotic excitement begins. Can these three girls get along?