ABOUT A BOY. By Nick Hornby. Gollancz pound;15.99.

Nick Hornby’s passions are contagious. Fever Pitch has been credited with (or blamed for) the reinvention of both football and the confessional novel as fashionable pursuits. But it would be unfair to pin the emergence of lad culture on Hornby as well. Lad culture ticks along nicely all by itself, and the sorry male specimens in High Fidelity must surely frighten off all but the most determined wannabe lads.

In Hornby’s first novel, Rob the record shop owner alternates accounts of his relationship traumas with his all-time Top Fives. I found myself making my own Top Fives between chapters (the Top Five favourite Hornby tracks I’ve never heard of but wish I had, the Top Five I must listen to again, the Top Five in the “he must be joking” category).

It seems likely that About a Boy, a sharp, moving social comedy, will engage readers in the same way and will do for young people what the first two titles did for Arsenal and vinyl (namely, remind adults why they are important).

The initial storyline has Billy Liar appeal. Will, whose commitment phobia is a few stages more evolved than Rob’s, invents a child in order to have no-strings affairs with single mothers. The ruse falls apart, of course, but in the process Will meets Marcus, a young teenager with a suicidally depressed mother, an absent father and no friends.

There follows an account of the friendship between a 12-year-old boy and a 36-year-old man who is not his father which pinpoints the power imbalance between children and adults in a series of typical Hornby twists.

It’s Will, not Marcus, who leads the life that many adolescents would die for. He lives on royalties from a naff Christmas song written by his father (Hornby has him mildly ashamed of this, but only on artistic grounds), does not have to work, and can buy all the CDs, trendy clothes and soft drugs he wants. He has devoted his considerable resources to acting cool and has missed what Hornby describes in Fever Pitch as, “the points at which one can choose to become an adult”.

While Marcus’s well-meaning but troubled mother gives him no choice about growing up, he is still a child lost in a scary new school. Hornby taught in secondary schools until his mid-twenties, and there are echoes in Marcus’s universe of the unease he felt as a new teacher in London. We can see the young Hornby (or at least the young self that he presented in Fever Pitch) in Marcus’s vulnerability but, while Hornby had his football, Marcus has no secret survival weapon. Having been brought up to be as unlike Will and his ilk as possible, he has no valid social currency to ward off the bullies until he is befriended by Ellie, three years older and all attitude and Nirvana T-shirts.

Hornby also recalls the effects of parents splitting up in Fever Pitch, but the “noise intended to express interest but no commitment” with which he greeted his father’s access visits seems to belong more to Will than to Marcus.

All Will’s instincts battle against allowing Marcus into a central place in his life, but Hornby makes use of Marcus’s viewpoint for a subtle analysis of the point at which Will finds it convenient to act his age. When Will says: “I can tell you who Kurt Cobain is and what trainers to get, and that’s it. Understood?” Marcus picks up the adult edge to “Understood?” and scales fall from his eyes. “He didn’t know any friends who said that, no matter how tall they were.”

At around the same time, his crush on Ellie evaporates because of her anti-social behaviour. “Ellie seemed determined to turn herself into him, and why would anyone want to do that? . . . maybe Ellie was like Will. If either of them had real trouble in their lives, they wouldn’t want or need to invent it for themselves.”

About a Boy is rooted in Hornby’s patch (mostly pages 45 and 46 of the London A-Z) which features Arsenal home games and Championship Vinyl (Rob’s shop in High Fidelity). When Marcus and Ellie break for Cambridge by train, it’s a doomed excursion leading to a denouement in a suburban police station complete with a riotous assembly of inadequate adults. But this is a universal tale despite its metropolitan sentiments (Marcus’s maturity goes hand in hand with becoming a Londoner) and presents a brutally honest picture of what it is like to be 12 and the caretaker of a depressed parent.

Such material is more often the preserve of fiction for children or young teenagers; without broken families and school bullies, entire children’s publishing houses would topple. Some writers transform adolescent troubles into art and may also help their readers through crises, but they are preaching to the converted; nothing will change unless adults jog their memories about what life is like for children, and few adults read children’s literature expecting to learn anything from it.

Nick Hornby is incapable of writing a worthy book, but this one, which will be read by adults in droves, is a rallying cry for the ultimate good cause of misunderstood youth. This is something Hornby cares about - he is a supporter of the mental health charity Young Minds.

A few F-words and disturbing scenes aside, About a Boy could be recommended reading for teenagers. It would be a shame to waste such home truths about youth on the grown-ups.