A ten-year old Japanese schoolgirl named Shinobu Omiya has a homestay visit in England, where she spends time living with a British girl named Alice Cartalet. Alice initially has trouble getting along with Shinobu due to the language barrier, but they soon get along swimmingly. As Shinobu's homestay comes to an end, Alice hopes that she will one day come to Japan. Five years later, Shinobu, who is now in high school, receives a letter from Alice, allegedly saying that she is coming to Japan. Surely enough, Alice appears at Shinobu's school, revealing she has transferred to her class and will be staying at her house.
Alice spends the day at school lamenting her short height whilst also developing a one-sided rivalry with their English teacher, Sakura Karasuma. Later, Alice goes on an outing with Shinobu and her friends Aya Komichi and Yoko Inokuma, before they try to figure out what to do for their future careers. Some awkwardness follows as Shinobu and the others assume Alice is homesick and try to help her out.
Whilst looking through an old photo album, Alice tells the others about her half-Japanese friend from England, Karen Kujo, who helped teach her Japanese. The next day, they actually come face to face with Karen herself, who had moved to Japan so she could study at Shinobu and Alice's school in the neighbouring class. As Karen gets along with the others, Alice feels a little jealous as Shinobu takes more interest in her. Whilst easily fitting into Shinobu's group, Karen has trouble making friends in her own class as they are intimidated by her foreign appearance. Asking the others for advice, Karen hears from the others about how Aya became friends with Shinobu and Yoko after transferring into middle school. Thanks to everyone's advice, Karen manages to speak clearly with her classmates and make lots of friends.
Despite it being her birthday, Shinobu feels a little downhearted following a remark from her sister, Isami. Later, Alice gets irritated when people see her more as Karen's little sister as opposed to a big sister. Whilst initially having some jealousy when Shinobu shows favoritism toward's Karen's present for her, Alice comes to realise that she loves Shinobu and Karen equally. Later, as Shinobu is off sick with a cold, Aya becomes anxious when Yoko receives an alleged 'love letter' in her locker, though Yoko assures her she would've turned down any admirers anyway. The letter turns out to be a letter Shinobu wrote for Alice's parents that she wanted Alice to translate.
After Shinobu embarrasses herself a little, Yoko explains how she often had to look after Shinobu in elementary school during times she was apart from Isami. Later, everyone gathers at Shinobu's home for a study session, before heading to the park so Isami can take pictures of everyone. The next day, Yoko gets relied on a lot and ponders if she is just a tsukkomi character, whilst also pondering how she views Shinbou as something of a little sister.
As summer vacation rolls in, the girls go on a trip to the mountains where they do some fishing and play about in the stream. Later, the girls attend a local summer festival, where they play at the stands. Whilst the others play with some fireworks, Yoko treats Aya's foot that had gotten sore from her sandals.
Alice has an exhausting P.E. lesson, not helped by her forgetting her tracksuit. Noticing Karen has gained weight since coming to Japan, the others suggest she go on a diet, only for Aya to get upset when she finds she weighs more than Karen. Later as tests come up, Shinobu gets Alice to help her study English and she manages to get an uncharacteristically good grade.
As the school festival approaches, Shinobu's class decides to do a Japanese/Western maid café whilst Karen's class is putting on a play. On the day of the festival, Alice reminds Shinobu that it is also the anniversary of the day she came to England, but can't find the opportunity to give her a present for the occasion. After serving various guests, including Isami, Shinobu's group to see Alice's class' unique take on Snow White. After the festival comes to an end, Alice eventually manages to give Shinobu her present, a ribbon, as thanks for the hairpin she received from her.
With her parents away for the night, Aya invites the other girls over for a sleepover, during which she ends up smacking away Yoko when she tries to touch her hair. Lacking the confidence to apologize to Yoko, Aya asks Karen to let her become her pupil so she can learn her energetic traits, but these don't suit her at all. After working up the courage to apologize, Yoko states she didn't think anything of the incident and buys some matching notebooks. Later, the girls play hide-and-seek in the school.
Sakura grows concerned over Alice's jealousy towards her over Shinobu. Later, as Alice gets hung up over horoscopes, the girls play some softball and visit a bookstore. On the weekend, everyone does their own thing, coincidentally meeting up along the way.
Shinobu invites everyone over for a Christmas party, with Alice happy to spend Christmas with Shinobu. After having a nightmare on New Year's Day, Alice comes to school speaking nothing but nonsensical English, worrying Shinobu. Alice eventually confesses that she was anxious about Shinobu losing interest in her because she was growing too accustomed to Japanese.
Upon the start of a new school year, both Alice and Aya become downhearted when they are put in separate classes from Shinobu and Yoko. However, Shinobu reassures her that the distance between them isn't any longer. After the credits, back to when the group were first year students, Karen starts to imitate a manga protagonist, prompting Shinobu to come up with her own story, in which she and Alice are princesses, Karen is a pirate, Aya is a mermaid and Yoko is a prince.
With their second year in full swing, both Shinobu and Aya are having trouble getting used to not being in the same class as Alice and Yoko, while Karen is intimidated by her classroom's strict homeroom teacher, Akari Kuzehashi. In reality, Akari wants to get along with her students but always seems to end up scaring them. Later, the girls try to learn more about Shinobu, later learning a little about how she got interested in foreign countries.
Akari continues to struggle with getting her students to like her. Meanwhile, the girls get together at Shino's house to make sweets for an afternoon tea party, though all manner of problems put them off their 'afternoon' schedule. Later, as Shinobu's class work on making some happis, Akari receives encouragement from the friendly Karen, managing to give off a sincere smile.
Yoko's younger siblings Kota and Mitsuki show up at school, inadvertently upsetting Yoko with a lie. Aya helps them be more honest and apologise, but has trouble putting her own advice into practise. Later, Alice starts to miss her pet dog back home, so the girls try to help her find a substitute.
Alice and Aya try their hand at being delinquents in order to appear more grown up, but this leads to Shinobu and Alice getting into a small fight, though they soon manage to make up. Later, Aya ends up trimming her bangs too short, becoming ashamed of her exposed forehead, while Alice worries about some flowers she planted a few months ago.
Noticing that Isami appears to be more spaced out than usual, the girls invite her to hang out with them on a photo-snapping day out to try and cheer her up. While depressed for most of the day, Isami soon returns to her usual self after saving Shinobu from getting hurt. Later, Alice, inspired by the tale of the Straw Millionaire, goes on a trading quest, eventually receiving a valuable ring from Karen, which she ends up trading with Isami for the one thing she considers more valuable, Shinobu.
The season of hunger (?). When Yoko nearly eats a plastic food sample, Karen suggests she takes on a super giant parfait. I may have been born for this! When Yoko gets overexcited, Aya can't help but interject.
Summer is coming. Drawn by its scent, Karen switches to her summer style! The others are confounded by her excessively wild style, and Karen trembles in fear when Yoko says the school might finally call her parents. Apparently Karen's mother is terrifying.
It's almost summer vacation. Yoko announces she wants to plan her summer, and this year she's going to the beach! But before they can enjoy their summer vacation, they must finish their final exams...
Summer vacation starts today. As Alice enjoys sleeping in, a suspicious figure approaches... Meanwhile, Aya borrows Yoko's summer assignment notebook to create a "No More Tears on the Last Day Homework Schedule!"
It's finally time to go to the beach. The girls can hardly wait. The excited girls are in high spirits as they head towards the beach. They're nearly at their destination!
It's the middle of summer vacation. As bright green trees sway in the wind, Honoka practices hard with her club. Due to her mysterious shouts featuring blonde hair, she's been playing especially well lately!
A green summer landscape. Cute honey-colored houses. Alice walks down a path with Poppy. Alice and Karen have returned to England. She'd glad to see her family again, but she still misses Shinobu. But the distance between them makes their friendship even stronger.