"You're gonna regret it if you stay with me". Oshima heard the rumors that his boyfriend, Hiyama, is quitting baseball. Upon hearing the upsetting news, and after being told that he's a nuisance to the baseball team and his boyfriend’s career, he tries to convince Hiyama to stay on the team. What will happen to their clumsy love story after they graduate high school?!

Takenaka's contract with his soccer team was suddenly cancelled, and he had broken up with his lover a while ago. The desperate Takenaka throws himself into Yamazaki's arms- a senpai that betrayed him when they were in school. When he sees no end to this lifestyle, memories of his inconsolable, bitter, frustrating days come flooding back... The long version of the oneshot "The abandoned town and you and I" is also included.

A high school teacher and a shy unpopular bishounen...Returning to his alma mater, Hiyori-sensei is still spending everyday alone. When he hears a rumor about a god of love fulfillment who can "make you fated to be with whomever you want," he makes the wish to meet his destined one. Afterwards, he runs into a younger colleague, Uzuki-sensei, and has an unconscious reaction in his lower half!It turns out that Uzuki is actually a former student that confessed to Hiyori 5 years ago. Now he's saying, "I still like you" ?!A bewildering love story!

The "240" in the series' title is pronounced "Nishio" as a reference to the writer's name. The manga celebrates the 15th anniversary of Nisio Isin's writing career, and it includes characters from Nisio Isin's works.

In every class, there is that one person who belongs to the flashiest group who can get along with any one. And on the other side is that one person who is always alone and that no one rarely talks to. In the classroom, you would never expect these two completely different types of people to meet. However, these two have more in common than they believe.

From Shinnen:

Isezaki, a second year from Kamiyama Boy's High, has had his heart captured by a girl he saw in the window of the neighbouring girls' school. A school route madonna!! After two months, it's time for her to graduate...?! It's a 17-year-old's summer starting from spring, chockful of idiocy and friendship enough to make you cry.

Also include is an extra story called Fuyu Hodoki in volume one.

What happens when your childhood friend becomes your teacher?

Konatsu Moa has been asked by the teacher to deliver the lecture notes to her mysterious classmate Yamada Kei, who hasn't been to school. Her childhood friend, Kisaragi Miyabi, decides to accompany Moa to Yamada's house only to find out....he's an otaku?! Their first impression gets even worse when he says some rude things to Miyabi. Will this unexpected encounter be start of the three's spring and romance...?

Makoto Toba hates everyone in his class. Everyone except, Sakura Touwa, an introverted high school girl who lives with her grandma and loves video games. But one day, Sakura disappears right in front of Makoto? Makoto has visited the site of her disappearance on the anniversary of her disappearance for the last 16 years. That is, until Sakura comes back from the time slip she was stuck in, and to her not a moment has passed. Now at 32 with a girlfriend, Makoto has to take care of his 16-year-old childhood crush. What could possibly go wrong?

Collection of short stories:
• Spring Egg
Chika’s house was actually just an old lodging house, but due to the location, her parents decided to turn it into a student dorm for the college students. One day, she meets her first love, Fujimori Tomohiro, a college student who will be living at her house! But, Chika’s mother had made him signed an agreement that he can’t go after Chika-chan?! How would their love bloom?!
• Sunflower Girl
Misaki likes Kenji but she doesn't have the courage to confess. Now that summer break is close, she plans to give him a love letter, but...
• Happiness Faces South!
Sakura used to like her sensei, but now that he has a girlfriend she decides not to like anyone else. Bon, a college student sees her playing softball and falls for her. Will Sakura be able to fall for him too??
• Prince and I
Mari has always liked her next-door neighbor Kaoru, but he always treats her like an old hag. Then Mari's sempai confesses to her. What will Kaoru do?
• 2 Block Honey
Satoshi's girlfriend used to be a crybaby, short and cute. That was a year ago! Now she's taller than him and likes to wear high heels. How does Satoshi feel?
• Spring, Air, Sunday

1-4) Seishun no Yamai wa - (The Sickness in Youth)
Successful businessman Minato is haunted by erotic memories of classmate Matsumoto and a series of embarrassing incidents from his senior high years. When Matsumoto reappears in his life as a new business associate, Minato's ordered life is turned upside down.

5-6) Tengoku ga Mieru - (Viewing Heaven)
Former bodyguard Kudo (introduced in Negai Kanae Tamae) is harassed by a nosy thief while on a trip to Europe.

7) Good Night
Minato encounters a helpful English-speaking driver when he becomes lost on an overseas business trip.

Due to changing schools constantly, Hime has been unable to make any friends. Now, at a brand new school, Hime sets out to celebrate her youth and live a dream high school life.

Right after the spiritually sensitive Takasago Daidai enters high school, he’s haunted by the mysterious ghost Sakuma Jun. They’ll solve the mysteries of the school and get Takasago his untroubled school life back!

From Dazzling Scans:
Hirata Mihane has a scary face and isn't ladylike at all. In fact, she lets her temper get the better of her and often lets out small bursts of violent behaviour—even though she doesn't mean to. Because of this, the entire school calls her a "Satsujinki" (murderous monster). Even so, she's in love with the kind and popular Touma-kun, who doesn't mind the way she looks and is always nice to her. But... will Touma ever see her as a love interest?

Spin off of Junai Tokkou Taichou! showcasing the romantic life of Hirata and Yusa's daughter.

Nagisa and her beautiful, intelligent best friend Yumi couldn’t be more different. Of course, her childhood friend, Ryou, is always happy to point this out whenever he can. When Yumi gets a crush on the equally intelligent and handsome Kei, Nagisa is determined to get the two of them together like any good best friend would, but it seems that Kei likes Nagisa’s outgoing personality more than Yumi’s shy one. And where does Ryou’s crush on Nagisa–and the one she may have on him–fit into all of this?

Every day Sakuta Gotou likes to zone out to his favorite band, Incest, because it makes him feel at ease. However, this band is very secretive and has yet to have a live performance. Now, when the chance comes to Gotou to see his idol Iive, the band's singer, on stage, he finds out that she is the new transfer student in the classroom next door... and to make this even better she stops the concert and grabs him saying, "I've wanted to see you." What is he going to do now?

Marking the end of one's youth--the high school graduation ceremony. Itsuki, the elder of the twins, spent the best graduation surrounded by friends and his girlfriend. Haruka, the younger of the twins, spent the worst graduation all alone. During the ceremony, the two accidentally fall from the roof--and find themselves back in time at the entrance ceremony. From there, the two's "retry" at youth begins.

In the beginning spring of high school life, "Sakono" Ikumi and "Sakono" Touma were utter strangers. The only coincidence is that they have the same family name and in the same class, but when they noticed the whole class had started to call them "husband and wife". This is a story of their love story in a husband and wife relationship, their youth days which lasted around two years and a bit.

Hoshiro, who had studied earnestly in order to impress girls with his brains, ended up in an all-boys high school! Now what? Well, it's off to the school's legendary wish-granting Tanuki Statue to pray for love! But what happens when his earnest wishes are overheard by the school idol?

From MangaHelpers:
A new program has been set in place for a certain area, where children are separated by gender into eastern and western territories. They're raised with no contact with the opposite sex, and made to only focus on their studies. Of course, there are a few bad apples, and the worst of these are sent to a co-ed school with the troublemakers from both sides. Unfortunately, this school soon became known as a place where the teenagers would battle to determine who was the strongest, and many boys and girls tried to be sent there.
At this school, the girls have an advantage, since the boys mysteriously get nosebleeds whenever they look at them. However, the strongest girl, Jun, is shocked to find that the strongest boy, Kyo, doesn't get a nosebleed when he looks at her! It turns out that both of them have had some experience with the opposite sex in the past, and they both have embarrassing secrets in the present.