NEVER BEFORE HAVE SO many children’s books been on the big screen. With even dusty old classics such as Nurse Matilda being given a new injection of life this month as Emma Thompson’s Nanny McPhee, and The Brothers Grimm being turned into a star-studded fairytale adventure, this year is working up to a frenzy of adaptation with the fourth Harry Potter and the first of C. S. Lewis’s Narnia stories both released next month. Following the success of Lord of the Rings, the Harry Potter series, the remake of Charlie & the Chocolate Factory and the brilliant film of Diana Wynne Jones’s Howl’s Moving Castle, Hollywood studios are scouring children’s fiction as never before.

What, though, should they be buying? For many children, there is no greater compliment they can pay a book than to say it would make a great film. We all long to see the impossible happen, and the kind of audience once happy to see Peter Pan fly about on wires on stage can now see utterly convincing Quidditch matches, dragons, mermaids and talking lions thanks to computer-generated effects. For others, seeing someone else’s imagination intrude on your own private Narnia is to lose part of its magic. Film, as fans of Harry Potter have discovered, speeds up the action and cuts enjoyable details. It can also take liberties with characters.

Computer-generated effects are both the boon and the bane of great children’s books. On the one hand, they can flesh out all the details of a magical world, whether the moving staircases at Hogwarts or an orc attack. On the other hand, they can come at the expense of character development and plot-line.

There’s no question that having seen the film turns many children on to reading the book itself, and when adaptations are as faithful as the Harry Potter films, the pleasure is reinforced. Where many people, rightly, resent and reject the bland Disney bowdlerisations of fairytales such as Snow White or Sleeping Beauty, modern directors tend to be more respectful, even when, as with Howl’s Moving Castle, directors insert preoccupations of their own.

At present, the fate of a number of modern children’s classics hangs in the balance. Philip Pullman’s His Dark Materials trilogy, after a troubled start, is undergoing a $4 million development by New Line (which made Lord of the Rings) and the director Anand Tucker, but afinal decision will not be made until January. Eion Colfer’s Artemis Fowl series, Jonathan Stroud’s The Amulet of Samarkand, Cornelia Funke’s Inkheart and Lian Hearn’s Across the Nightingale Floor have all been bought by big studios but are in development limbo, with scripts at various stages and no stars attached. Much as children yearn to see them made, they can yet fall foul of the Byzantine process of getting backing. As one talent scout for Miramax said: “You have as much chance, statistically, of being struck by lightning as of actually having your novel made into a film.” Yet as studios have discovered, a good children’s film makes money like nothing else.

Nick Marston, the film agent for Curtis Brown, says: “Studios are obsessed with making their product as inclusive as possible. If they can make a film that can play well to a five-year-old and their parents (or even grandparents) and all in between, then obviously that’s the ideal.

“The problem is that for children’s films to work, it does seem that you have to spend huge sums. The budget on Charlie and the Chocolate Factory went enormous. ‘Indie’ children’s films don’t really work. British attempts to do originals (Thunderpants) or adaptations (Five Children and It) without the studio backing haven’t recently worked.”

Antony Harwood, also an agent and the son of the Oscar-winning scriptwriter Ronald Harwood, says: “I don’t believe the boom in interest has anything much to do with a shift in taste or demographics or CG-technology. Films aimed at children, at families, have always done good business — look at the top 20 highest-grossing films of all time and all but four or five are in the ‘family viewing’ category. Families, after all, make great consumers: they not only go to the cinema but also buy DVDs and the merchandising.” ()

It’s a shrewd point. Yet studios can pour millions into merchandise and still find it fails to fire any enthusiasm. What is interesting about children’s films now compared with the Disney hits of a decade ago, is that they seem to be being driven from the bottom up. Anthony Horowitz’s Alex Rider series about a reluctant teenage James Bond had been stuck in development for years — signed up to be directed by Chris Columbus, the first Harry Potter director, then dropped. But when Black’s The Ultimate Book Guide published its list of the books children most wanted to see filmed, and Horowitz’s Stormbreaker came out as No. 1, the last doubts fell away. Stormbreaker, starring Alex Pettyfer, has at last been filmed. It is the most expensive children’s film ($40 million) ever made in Britain, but its success next summer is pretty much guaranteed. Whether children will feel the same about Charlie Higson’s Young Bond series remains to be seen.

One effect of the Harry Potter phenomenon is that children seem much more aware of the power they have to make things happen in Hollywood. I asked Roger Mortimer, Head of English at Highgate School in North London, and himself a children’s author, to get 96 pupils in Year 6, 7 and 8 (aged from 10 to 13) to say what books they would most like to see become films. The answers were intriguing.

The only established children’s classic to feature was The Hobbit, which tied with Michelle Paver’s Wolf Brother in second place. The horror writer Darren Shan was popular, as was Eoin Colfer. Anthony Horowitz’s other novels were on almost everyone’s wish-list, as was Christopher Paolini’s sub-Tolkien fantasy, Eragon, and Nancy Farmer’s Viking adventure, Sea of Trolls. The surprises were Caroline Lawrence ’s Roman Mysteries, Mark Haddon’s The Curious Incident of the Dog in the Night-Time and Malorie Blackman’s Noughts & Crosses — thoughtful dramas that challenge how we see the world.

There are a number of great children’s novels that it is hard to see working on screen. Philippa Pearce’s A Dog so Small, David Almond’s Skellig and Lucy M. Boston’s Green Knowe series all feature dramatic events, yet the drama is so internalised that they would require child actors of genius. If too many adult writers trying to break into the children’s market make the mistake of writing scripts rather than novels, it is worth remembering that some of the great classics, which will outlast the immediate hits, will always be best on the page.

Which books should be made into films?

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