Jack Gantos must be the only children's author who has spent 18 months in prison for smuggling drugs. He's already written about that incident in Hole in My Life; his latest novel, Dead End in Norvelt, which has just won the Newbery Medal and been longlisted for the Guardian children's prize, fictionalises an earlier stage in his life.

The hero is Jack Gantos, a plucky 12-year-old living in Norvelt, the small town in Pennsylvania where Gantos himself grew up. It's the summer of 1962; John Glenn has just orbited the Earth and Marilyn is about to die.

The novel initially appears to be a fairly straightforward description of an American childhood in the early 60s. Jack is an ordinary kid who makes the mistake of borrowing one of his dad's souvenirs, a rifle looted from the Japanese, and doesn't realise it's loaded. As punishment, he's grounded for the entire summer. His mother only lets him leave the house to run errands or help Miss Volker, an elderly neighbour who writes obituaries and a history column for the local newspaper.

She gives him an education in a side of American history that would otherwise be hidden from him, telling him, for instance, about Alexander Berkman and Emma Goldman, "two great American anarchists who wanted to improve the lives of all Americans". There's a simple reason, she explains, why Jack has never heard of them: "Schools don't teach the history of social reformers who were real American heroes and fought for workers' rights and justice."

Gantos has a relaxed style and writes very enjoyably, peppering the pages with good jokes and eccentric characters, but it soon becomes clear that this isn't simply his reminiscence of a charming childhood; the real hero of the novel isn't Jack himself, but his home town and its values. Norvelt was a New Deal town built by the US government to house poor families and named after Eleanor Roosevelt, described by Miss Volker as "the greatest American woman who has ever lived".

Miss Volker explains the inspiration behind the town: "Jefferson believed that every American should have a house on a large enough piece of fertile property so that during hard times, when money was difficult to come by, a man and woman could always grow crops and have enough food to feed their family. Jefferson believed that the farmer was the key to America and that a well-run family farm was a model for a well-run government. Mrs Roosevelt felt the same. And we in Norvelt keep that belief alive."

Miss Volker has lost the use of her hands, so Jack types the obituaries for her, and these histories of the townspeople, who are now dying off, form the heart of the book. There's a murder-mystery plot wrapped around the deaths, but Gantos deals with it perfunctorily and doesn't seem particularly interested in the usual mechanics of plotting. His main interest is the lives of his characters, not their deaths.

Dead End in Norvelt is a defiantly political novel that delivers some simple moral messages: question the stories that you're told at school or in the media; "if you don't know your history you won't know the difference between truth and wishful thinking"; and, most importantly, don't forget the narratives of American life that have been neglected or deliberately buried by the dominant culture.

 Josh Lacey's The Dragonsitter is published by Andersen.