It's about an odd girl doing odd things.

In the Mazinger Otome series:

V.1 - Mazinger Otome

V.2 - Mazinger Otome Taisen

The story starts with a seemingly unassuming class rep Adachi Hana who has taken an interest in the school's known delinquent, Shinagawa Daichi. Just what is her reason for following Daichi and wanting him to go on the class field trip?

Included in volume 11 is the story called Fairy Megane, a crossover between Fairy Tail and Yanki-kun to Megane-chan.

A spin off based on Ai's usual antics of "trying to get closer to Ta-kun" from even before affiliating herself with the Jien Otsu club.

Tsubaki is a girl who loves making her younger sister's hair pretty every morning, but she doesn't think that kind of style suits herself! The day of her High School Beginning Ceremony, after she failed in being the top student (who usually makes the ceremony speech), she finds herself sitting next to the actual top student of the first years, the worst rude guy ever, Kyouta. She ends up cutting his hair on purpose because of the bad things he says to her. Kyouta demands that Tsubaki pay him back with her body, but Tsubaki fixes his hair instead--making it even shorter! After that, Kyouta unexpectedly kisses Tsubaki and swears that he'll make her his woman.

Sumire is a 17 year old high school girl who wants nothing more than to make friends with her new classmates. She's so disappointed that they all seem to hate her, calling her a pervert, a dirty old man, creepy, weirdo... alas, what is a poor life-sized puppet to do in this cruel world.

Katsuragi Keima is known on the net as the god of getting the girls while in real life he’s known as otamegane and he hates all real girls. However he is approached by Elsie, a devil from hell, to help her in catching runaway spirits that hide in people. Apparently the spirits only hide in the hearts of girls and the only way to get the souls out is by making the girl fall in love so the spirit gets forced out. And he’s not allowed to fail or he will lose his head.

From Entropy:

Ageha is a high school student who has taken over the role of housewife ever since his mother passed away. He has two younger brothers whom he must care for, and a useless father who is always out dating women.

There's a girl that Ageha likes--his classmate, Nina. She tells Ageha that she's in love with a handsome, popular singer. Ageha decides to sing on stage at an open mic session to prove to Shinna that he can be like that guy, too. But just after he starts to sing, someone interrupts and abducts him! The stranger is no other than Miyamoto Range, the singer whom Nina loves.

Range wants Ageha to join the Shibutani Alliance Cub—his band—and is relentless in his pursuit. At first, Ageha thinks that Range is annoying. But little by little Ageha is won over by his charm. Will he be able to accept Range? Will Nina ever return his feelings?

From: Easy Going Scans

Our protagonist Jo Cheul-Hee is a delinquent who enjoys picking fights and aims to take control of his new school where he gets transferred, but what he doesn't know is that it's an all girls school.
Being the only male student there, everyone thinks he is gay!

From Delish Scans:

Facial communication, no words necessary.

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Two children, a girl and a boy, pass each other on the way to school, everyday at the same exact place, at the same exact time. They never talk only making funny faces at each other. But one spring, something's bound to change...

Fat school delinquent meets cute, shy girl.

When their high school’s pop-music club is about to be disbanded due to lack of interest, four girls step up to fill the membership quota. Unfortunately, lead guitarist Yui Hirasawa has never played an instrument in her life. Ever. And although she likes the idea of being in a band, standing in front of the mirror posing with her guitar is a lot easier than actually playing it. It’s gonna be a while before this motley crew is rocking out, but with their spunk and determination cranked to 11, anything is possible!

Kurosaki Sou is a 16 year old who summons a devil to take his virginity. He hopes for a devil with flaming red hair, large horns, and black wings. He gets exactly what he wishes for, although he forgets something else rather important. Now he’s forced to live with this devil and has to think of a way to get rid of it, and most importantly – survive its lust.

Amano Hinata, a high-school boy, lives a quiet life in the country. One day, a light-haired transfer student, Kazama Ayato, arrives from Tokyo. In such a small town, it's not long before Hinata runs into the laid-back, absent-minded Ayato, along with his lively younger siblings: Hayato, Ikuto, and Chiyoko. It's going to be quite a challenge for the Kazama family to assimilate into their new community out in the country!

From Tokyopop:
Young Mikan runs away to Tokyo to follow her best friend, Hotaru, who has been enrolled in an exclusive, secretive private school for geniuses. But it turns out that Alice Academy is a lot more than meets the eye. If Mikan wants to stay by Hotaru's side, she has to both pass the strange "entrance exam" and face the even greater challenge of befriending her very odd new classmates. Whether it's Hotaru's gift for inventing gadgets, the cranky Natsume's fire-casting ability, or Professor Narumi's control of human pheromones, everyone at the school has some sort of special talent. But what ability, if any, does Mikan possess? Mikan is going to have to rely on her courage and spunk if she's going to stay in school, or even stay alive!

From Nigihana: One day a high school student named Haruhiko who is aiming for Tokyo University has discovered a very important secret. From the closet, appeared a beautiful girl with a black pony tail, Utsuki who came from "Moon Village" with her Ninja Troop said to him, "It's been 7 years, master."

From Nagareboshi Manga:
Sachi has always been known for her gorgeous amber-colored hair that she inherited from her mother. She has a happy enough life, except for the fact that her mother is dead, which she keeps a secret.
One day, she is approached by a classmate who seems to know all her family's secrets, and is forced into his "Money Game".

This year, the student council has decided to add an exciting new contribution to the school's culture festival; an Idol performance! However, they don't actually have the money to hire any real Idols, so someone's going to have to train up an idol group from their female classmates. Hirano Harufumi is that unlucky someone. He has no interest in Idols at all, but he must put together a performance or risk expulsion from the school for his failure.Not surprisingly, most high school girls are too embarrassed and self-conscious to dance and sing in front of their classmates in a skimpy outfit. When Harufumi tries to think about who he would like to see as an Idol, his thoughts are drawn to his cute, shy, clumsy childhood friend Aizawa Momoka. Will Harufumi be able to convince her to be an Idol before it's too late?Sequel:> Atashi no Idol ( http://mangapark.com/search?q=atashi-no-idol )

1) Love Making
Student Shinobu loves cafeteria food and usually cleans his plate, the only thing he won't eat are carrots. When school nutritionist Tatsuya catches him throwing out food, he has to think of a creative way for Shinobu to eat his vegetables...

2) The Pigheaded Deity
Keisuke's grandfather always warned him about the Tengu living on the mountain, but that was when he was a child. Keisuke's an adult now, so why is he seeing a handsome man with wings?

3) Let Me Drown in the Sea of Love!
Atsushi is a failing romance novelist whose active fantasy life has wrapped itself around fish shop employee, Sakurai. Can Atsushi wake up long enough to make a move?

4) God, Give Me a Wife
Kurachi Daisuke is a high school teacher with a problem: he's single. So he prays to the heavens to give him a wife, when a passing alien hears his wish and decides to help, Kurachi may have to think a little more exotically about him love life.

5) The Kind Hearted Roommate / Oshikake Hunter
Dorm head Hiroki never expected Kenta to come to his school. Hiroki always treated Kenta as a younger brother, but Kenta's feelings were far from brotherly, and he's not going to let Hiroki slip through his fingers again!

6) Dealing with Fate!
High school student Tetsuya has a really bad memory, especially first thing in the morning. This leads to a mix-up on the street and Okada Aki enters his life.

7) Diary of a Fantasy Life!

8) Love Making II
Tatsuya has started a new job at a college and Shinobu is lonely.

A short 4-koma about a girl with a mean look and her two new classmates.