Freedom Writers is based on the true story of a group of high-school students in Nineties, gang-torn LA, who produced a collection of Anne Frank-inspired diaries about their experiences in the ghetto.

These kids had been written off by the education system. Thanks to an indefatigable young English teacher, they wrote themselves into history.

This being a Hollywood product, the (white) teacher, Erin Gruwell, played here by two-time Oscar winner Hilary Swank, predictably takes centre stage.

No one's disputing that the world needs inspirational inner-city instructors. But films about them? Oh please, shoot me now.

Freedom Writers is the antithesis of the recent black comedy, Notes on a Scandal, in which a similarly idealistic, beautiful and inexperienced teacher unleashes chaos in the classroom.

Erin, by contrast, whips up a safe haven, a place where tears flow as easily as Biros. Initially hostile, da kids are soon under her spell, all but running through the street yelling "praise her!"

And yet - gulp! - I found myself moved. Swank made her name playing white-trash tomboys and being cast against type is clearly good for her. She was gripping as a socialite in last year's Black Dahlia and here, playing a preppie overachiever, she's superb.

Imelda Staunton is also impressive as Erin's "old-school" head of department - a very human monster, boasting a deadly smile and a body quivering with sadness.

As for the kids, they underplay things beautifully, with newcomer April Lee Hernandez outstanding as a Latino toughie. She's short and stocky, so will probably never be heard of again.

Gruwell's big idea was that her kids were as much victims of war as Anne Frank (hence the diaries) and, thanks to the indefatigable cast, this apparently far-fetched notion comes to make perfect sense.

Freedom Writers is a soft-bellied drama with a hard-headed message: Holocausts are still happening, right under our nose.