"An Education" is just what the title promises, and a delight, as well.

What do we learn? Something about the role of women in early 1960s England and a lot about Carey Mulligan, who is fantastic as a precocious teenage girl whose eyes are opened to the possibilities of life beyond suburban London by an older, not entirely scrupulous fellow (Peter Sarsgaard).

It has the potential to become ugly or unseemly, but the direction, by Lone Scherfig; the script, by Nick Hornby (based on Lynn Barber's memoir); and, especially, the performances prevent it. Instead, though the movie has its edgy moments, it's remarkably entertaining.

Jenny (Mulligan) is 16 years old in 1961, on track for Oxford, thanks to her own considerable intelligence and her overbearing father, Jack (Alfred Molina, very good). She's the best and brightest student in her strict girls school, but she's aware there is more to life, even if it's not currently available to her.

That changes with the appearance of David (Sarsgaard), a man in his 30s who spots her standing in the rain and offers her — and her cello — a ride home. He's smooth, worldly and not immediately threatening.

She's smitten, of course, not just because an older man shows interest in her, but because he knows so many things. Jazz, Paris, sports cars — London wasn't quite swinging yet, but David seems well-equipped to get in on the ground floor.

David manages not just to charm Jenny, but her parents, as well. Jack is as taken with him as Jenny is, easily distracted from his insistence on a proper education if Jenny can marry the right man. And David seems to fit the bill.

He doesn't really, of course, and Jenny learns this pretty early on. Yet, rather than break things off, she continues the relationship. If David is somewhat pathetic, trying to use Jenny, she uses him right back, mining their time together for experiences she certainly couldn't have otherwise.

It's a scandal at school, with the icy headmistress (Emma Thompson) warning Jenny sternly — her default demeanor — that no good can come of this. Somewhat more compassionate is one of her teachers, Miss Stubbs (Olivia Williams), who genuinely wants to see Jenny succeed.

But how is success measured for a woman in 1961? That's the question Jenny struggles with, and it informs every decision she makes (though she doesn't get to make all of them). Mulligan is great, as is Sarsgaard, but they're aided greatly by the larger context of oppression and dead ends that Jenny faces. You almost wish Jenny could scream, "Wait eight or nine years and tell me how misguided I am!"

Alas, no such luck. The frustration that she feels gives "An Education" much of its power, even as Mulligan's portrayal of the wonderfully complicated, self-aware Jenny makes it an awful lot of fun to watch.