The animated opening credits of An Education promise untold delights, to us and to the movie's heroine.

Martinis and phonographs, jazz and Paris — these are the tokens of adult bliss if you're a smart, bored 16-year-old girl in 1961 London. They come with a price, of course, since what coming-of-age movie lets its main character off scot-free? That Lone Scherfig's wise and engaging drama runs so smoothly on its well-established rails is its pleasure and its limitation.

British actress Carey Mulligan plays all sides of schoolgirl Jenny in the same quicksilver breath: the clever A-student, the arch young cynic, the Left Bank existentialist wannabe, the naive girl, the lover, the fool. Comparisons have been made to Audrey Hepburn and when Jenny piles her hair up in one scene for a walk down a Paris sidewalk, you may be dazzled into agreement.

A star may or may not be born in An Education, but an actress most surely is.

When the movie begins, all is going according to plan: Jenny is acing her studies and extracurriculars and seems unstoppably Oxfordbound. After that the vision of her parents and schoolteachers turns cloudy. Presumably Jenny will marry a social class or two above her, which is what matters. For herself, she sneaks smokes, listens to Juliette Greco albums, and yearns desperately to be French. The film captures the moment before the Beatles arrived and changed everything, when post-war England was a dead end and to be young was to dream of escape.

Then Jenny meets David (Peter Sarsgaard), who is not part of the plan: 30-ish, Jewish, charmish. He has a sports car and smart suits, and what he does for a living is interestingly vague. He knows coloured people; he can talk jazz and classical; he has been to Paris.

Of course the girl is headed for a fall. Life sometimes works the other way, but movies don't. An Education takes its title seriously enough that you know what's going to happen. The final half hour feels especially formulaic, as if the director has glanced at her watch and realised she needs to wrap things up. Jenny deserves better than the cliches that overtake the script.

An Education lives through its women, though: Rosamund Pike's sweetly dim Helen, Cara Seymour's trapped but caring Majorie, Olivia Williams as a teacher whose dowdiness is only skin-deep, Emma Thompson in a brief turn as a headmistress with spine and head of iron, Sally Hawkins in a briefer turn as a young mother. To Jenny they're all the possible Jennys she might turn out to be if she doesn't forge her own path.

The title refers to at least three meanings of "class" — the school courses she takes, the social classes she intends to cross, and the personal class, the inner elegance, Jenny seeks in Helen or Paris but which already resides in herself.