I saw this on the plane and loved it. I realise that it's hardly the first film ever made in which an unconventional teacher inspires his student(s) to feats that surprise even them, but it's funny and lovely.

It's also based on a bestselling novel, which in turn was based on a true story. Its author was writing about his own experiences bringing one of his pupils up from near zero (the equivalent of primary school level) to winning admission to the internationally famous and highly competitive Keio University in only 18 months. Knowing this adds to the experience of seeing the film, I think, but from now on I'm going to discuss it strictly as fiction.

Sayaka Kudo (played by Kasumi Arimura) is a bimbo. What's more, she enjoys being a bimbo. She chose to become one. We follow her life from an early age, when a genteel but indomitable mother (Yo Yoshida) and a couple of unfortunate incidents ended up putting her in a position where she'd effectively been told she didn't have to study. Yoshida's the kind of mother who'll back you no matter what. She'll always support you. Always. It doesn't matter if you're right or wrong.

Anyway, Sayaka lives to goof off with her friends, is openly at war with her schoolteachers and redefines the word "ignoramus". She's the kind of person you could imagine being surprised to learn that the world isn't flat. However she's also great fun. She's chirpy, enthusiastic and oddly charming in her cluelessness. (It also helps that Arimura is adorable in the role.)

One day, Sayaka manages to get herself indefinitely suspended from school. Her mother buys her private tuition at a cram school, with her teacher being Yoshitaka Tsubota (played by Atsushi Itou). Yoshitaka is wonderful. He's a nerd whose lack of cool is a running joke in the film, but he's wonderful. You see, at school he too was a failure. Everyone bullied him and he believed what they said, so he assumed he was worthless. Now, he does one-to-one personal tuition with problem students, with a philosophy that's based on being super-positive and encouraging the students to believe in themselves. He'll tailor his teaching methods to each pupil. He'll study video games in order to be able to talk like a gamer to gamers. He'll find psychological hooks to persuade dead-end students that they have a reason to keep trying after all. He'll also fight tooth and nail against people who dismiss no-hopers as no-hopers, because the likely outcome of pinning that label to someone is that they come to believe it... and then they really will be no-hopers.

Sayaka's schoolteacher is reptilian, by the way, even though his opinions are understandable and even probably normal. Ghastly man.

Do you need me to continue? You've already predicted most of this film's plot, bar one or two wrinkles. There's a subplot about Sayaka's brother, who's suffering at the hands of their father. The father's trying to push the brother into becoming a professional baseball player, despite the facts that (a) this was always the father's dream rather than the son's and (b) the odds against success in this are on a par with Sayaka raising herself from one of the worst students in the country to one of the best. A secondary theme in this film is the conflict between dreams and reality. Trying hard doesn't guarantee success. "Give up on your stupid dream" is said to more than one person in this film.

It's also surprising how many people turn out to have damagingly low opinions of themselves. "I'm nothing." Adults talk of humiliation when they really mean something worse. Meanwhile the magic pixie dust in the air at Keio University is confidence. The students believe they can make something of themselves and they're well down the road to doing so.

What makes the film lovely is its warmth, its humour and the strength of its message. It's very funny. It's very clear about what it's saying, to the extent that wrong people might call it preachy. Above all, though, the characters are great and you can empathise with everything they put themselves through. Sayaka's mother is almost heroic. Sayaka herself is a delight to watch, always bursting from the screen with vigour and opinions. And then there's Yoshitaka, who's a silly, klutzy man who transforms his students' lives. I also specifically love the Yoshitaka-Sayaka relationship, which derives much of its power (I think) from the fact that there's nothing underneath it. There's a simplicity to a teacher-student relationship that would actually be damaged by turning it into a romance. (The film doesn't go there, thank goodness.) Yoshitaka's putting his all into trying to help Sayaka, but it's no more than he's doing for all his students. It's not personal, except of course in the sense that one-to-one tuition is inherently so, especially with all the effort he puts into it. Put Yoshitaka in his classroom with anyone and he'll be morphing himself like a little dorky clay doll, putting all his energy and ingenuity into finding the best way to help the other person.

And I love Sayaka too.

There's nothing I'd change about this film. Well, maybe it could have been tightened up a little in the closing stretch, but only a very little. Disclaimer: I used to be a teacher myself, so maybe I responded to it particularly strongly. Well, I probably did. I still love the film, though.