It took a film director to turn Frank Cottrell Boyce into a children's author. He talks to Dina Rabinovitch about scripts, nuns and the gap between reading and writing
Framed by Frank Cottrell Boyce
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For many people, writing a successful screenplay would be enough. There wouldn't be any need to experiment with other art forms, like children's books.

Frank Cottrell Boyce, who won the Carnegie Medal with his first novel, Millions, and was shortlisted for the same prize with his second, Framed, has 12 movies to his name, including Hilary and Jackie and last year's Steve Coogan vehicle, A Cock and Bull Story. It wasn't until he reached his forties that he swerved into full-time children's writing: 750 words a day, leaving time for rewriting in the evenings.

Maybe it's all the children. Cottrell Boyce arrives at my house, en route to the Blue Peter Studio, with three of his clan in tow. He met his wife Denny at Oxford, where she was set on becoming a nun, talked her out of that, and now there are seven eloquently named kids. "Cottrell Boyce" is Frank and Denny's other amalgamation, their two surnames joined as one.

The family live in Liverpool, with the youngest ones home-educated by Denny - which is partly why they can come along when Dad's being interviewed. Cottrell Boyce, in natty pale tobacco-coloured trousers ("my friend's got a designer shop") and a baggy, collarless white shirt, sits at my kitchen table while the children run off to explore.

Both of his children's novels are on a big scale - wildly filmic adventures set against family life. A boy finds a million dollars at the bottom of the garden; art treasures and the perfect crime. "I've got kids," Cottrell Boyce says laconically, "I already have a constrained domestic existence. Most of my life is at home or standing outside schools - so of course I wanted to write big adventures, not school gates dramas."

Millions was actually a filmscript he'd had knocking around for ages before Danny (Trainspotting) Boyle picked it up. It was over dinner with Boyle that Cottrell Boyce realised there was a book in the ancient script too. Boyle wanted to know why he didn't write for children. "He just asked me why I hadn't done it," says Cottrell Boyce. "So I said, 'well, I've never had an idea for one.' And he said, 'well, Millions ... '"

It was a light bulb moment. "I'd only ever thought of it as a film," explains Cottrell Boyce. "Cos a film doesn't ever let go of you - it's like a task to be solved. It's not like it came to me as a story that you could do many different things with - like, now, it's a play in Germany! But it never struck me as a 'story', it just struck me as a movie.

"Well, I don't think like that any more - but that's down to Danny. He has that quality - he asks you to do something, and you do it, an ability to ask more of you than you realise you have inside you. Our boys had a violin teacher like that once."

That night, Cottrell Boyce went home and bashed out a first draft.

It was the nun who taught him in Year 6 that he credits with turning him into a writer in the first place. Sister Paul read some of his work out to the class. "Instead of asking me to read it, she read it," he remembers. "And it got all the laughs in the right places. And that was the first time I had a sense of somebody writes, and somebody else performs - a vision of that little gap.

"It was about Vikings, but I'd put jokes in. I just have this very vivid visual memory of being at the back of the class and seeing people's shoulders going up and down, laughing, and me being at the back of the class and them not looking back at me. I remember thinking that was delicious, that you could be in the limelight, but invisible."

He has come to relish meeting his audience face to face - kids coming up to him with copies of his books filled with polaroids showing they've retraced the locations in the stories. "They give you your books to sign with their fingerprints all over them, and you can see how much they've loved the book."

It took a film director to turn him into a children's author. It's taken a children's author to persuade him to write another screenplay. He was sitting on the panel for a discussion of adaptations with Michael Morpurgo, but Morpurgo, not one to miss a trick, canvassed his fellow author for a film script instead. "He took the same approach I'd used to get Denny away from the convent and into marrying me. He spent most of the afternoon just saying, 'so, you'll do the script for Kensuke's Kingdom then?'"