From ShoujoMagic:

Karate girl Seri tries to kick away her past in order to catch a new guy at a singles party, but Tamaki, a childhood flame from her old karate dojo, shows up to show off and makes her heart pound. Their reintroduction leads to a karate challenge, and if Seri loses, she must become Tamaki's "toy"...!? It's a game of love with more rivals and obstacles (and sex!--LOTS of SEX!) than either Seri or Tamaki could have foreseen!

Includes extra stories:

(Vol.02) Virgin Beast - Dumped for being a virgin, Katsuragi Mio decides to ask Virgin Killer, Tsukahara Masaho for help.

(Vol.03) Scarred Innocence - Naive Moeka wants to fall in love but Kamiya Shun might not be the nice guy she thinks he is.

(Vol.04) A Girl's Mischief: Love's Supreme Principle - Renai Shijou Shugi sidestory.

(Vol.05) Rescued Letter, Complicated Love - Nozomi delivers a love letter to Shigeyama Itsuya from her friend but...

(Vol.07) Ribon

(Vol.08) Flower of Despair, Thorns of Pleasure - Renai Shijou Shugi Sidestory. Takarai Kou's point of view.

The curse of twelve stars, a girl who plays piano with a dream of becoming a chef, because of an odd job that she pretends to be a boy. What's waiting for Yue Hui is a mysterious mansion and 12 boys who have the curse of 12 stars which fall upon each of them. What's awaiting her? Where are her and the boys' destiny leading to? A love song for 1000 years, the legend of 12 beautiful stars, everything is in《Starry Night Club》

From Summer Rain:
Seo has been in high school for little more than two months. She likes schools that allow casual clothes. However, the annoying, stupid guy, Narusawa Shin is really hard to deal with. Could such men really be?!

A short one-shot about a student council president who seeks to be an "onee-sama".

A story of a vampire who might disappear like smoke and a girl who loves money.

17-year-old Saitou Ken joins the student council filled with otaku... specifically BL fan-girls...

From author's site:
I love math. Just after the high school entrance ceremony I meet a beautiful girl, Milka. Milka is a mathematical genius. She gives me many math problems and shows me many elegant solutions. Milka and I spend a long time discussing math in the school library.
A year later I meet another mathematical girl, Tetra. Tetra is one year younger than me, and asks me to teach her math. While I teach her, she begins to understand math and to love its elegance gradually."

The first series is about Fibonacci Numbers, Harmonic Numbers, Finite and Infinite Sums, Factorization, The Basel Problem, Partitions of the Integer, and Generating Functions.

Alien invasions come in all shapes and sizes. This time, the Earth is under attack by "Unknown Codes" that infiltrate digital devices to eviscerate the human race. The only known way to counter these codes is to play their own game. An awkward mesh of men with different motives are recruited to fight. How is everything going to end?

From Keijo Shoujo Scans:

Sumire is habitually indecisive. Kei is brutally straightforward. And so begins a sweet, high school love story.

One day, Shiro and his little sister, Koyori, who has been permanently crippled after an accident, download a peculiar game called "Strings Dolls." Whenever you have someone in your camera screen, the game allows you to move them around like a puppet. Shiro and Koyori are filled with joy to realize that this magical game can restore her ability to walk, at least temporarily. However, other people use it for much less noble purposes. Among the others who have downloaded the game is a mysterious player called Miyabi, who appears to use the game for PKing. Will Shiro be able to track down those behind this game and find the murderous Miyabi before it's too late?

From Osuwari Team:
“I want to get a boyfriend in high school.” Born on the same day, at the same hospital, Asuka and Tomaru were always together. Though they seem more like twins than real twins, Asuka’s desire for independence means separation… a complicated situation?!

From JShoujo Scans:

When Ageha was younger, she watched a tennis game and was affected by a passionate young tennis player. Years later she was determined to become the number one tennis player and to join the tennis club in her new high school.

Amasawa Miyako, the middle child of 5 siblings, is the only 'normal' one, the others all being very good-looking and very talented at something. She takes care of them at home with cooking, cleaning, etc. because their parents are very busy at work, but she has to deal with both her own insecurities and people's opinions on how she's not like her brothers and sisters. It also doesn't help that she likes her best friend who's in love with her older sister...

Note: Ch1-2 released by Bad Eggs are Volume 2 chapter 2a and b.

Note 2: The 3rd and 4th chapters are the oneshot called: Sora no Mannaka ~Spring Storm~

From Attractive Fascinante:

The infirmary sensei, Odagiri, always said that students were out of his strike zone. One of the students, Izumi, kept coming back to seek a physical relationship with him. He heard that Izumi was a player, but he soon realised that it was Izumi’s first time when they started to feel each other up. Odagiri stopped at that very moment and told Izumi never to look for him again. However, Odagiri got upset when he saw Izumi flirting with another student. Was it love?

From Midnight Scans:

Aoi was abused by her teacher in middle school, a trauma she is still unable to overcome. One day, because of a family vacation, she is reunited with her first love, Kaoru: even though she has never forgotten him, she definitely doesn't want him to see how much she's changed...!

'Recently, the social evils have not disappeared yet and they are even contagious into the school' is what Soo Yung believes, little does she know that the 'accidental' first kiss on the school roof leaves her running/craving for more!

All three of Mao's high-school girlfriends have been taken away by the gorgeous-looking Yuu. But in retaliation to the slap that he gave this popular guy, a confused Mao gets a kiss..!? Soon he's dragged into the world of the school's "celebrities," who all have special talents, which range from "entertainment" to cosplay, and even pleasure!

What has Mao (unwillingly) gotten himself into?

From Sweet Love:

It was her 16th birthday when Kurusu's classmate, Ogami, confessed to her. She’s delighted, but also feels very uncomfortable in relation to her friend Kiraha, whom she knows has a soft spot for this guy. But Kurusu doesn’t have any time to rejoice, because mysterious evil creatures suddenly appear and attack her!! Kurusu must face her destiny along with Ogami, whose role is to protect her. However, they can't tell Kiraha about the situation.

1-3. Hana Sakasemashou (Let the Flowers Bloom)
Yasukado and Yasutoki are twin brothers born as the heir and protector of their family's feudal household. When an assassination attempt is made on Yasukado, Yasutoki must do all he can to protect his beloved brother and lord.
- Blissful Sin

4. Futago no Goshisoku-sama
An alternate story of Yasukado and Yasutoki in a modern world.

5. Suki ni Nattara!

Lotus Girls' Academy. A school whose aim is to educate young girls to be pure and modest. Youko is a new transfer student here, and immediately takes a liking to Shuu, who shows her around the school. However, Youko discovers a big secret about Shuu... she's a vampire! Youko then does her best to be the best friend she can be and help Shuu protect her secret... whether Shuu likes it or not! But how does Shuu really feel about Youko... and why does her blood taste so different? And to what lengths will Youko go to help Shuu?