THE wonderful thing about children, says James Campbell, is that they're great at heckling. Even better, they're not bothered about turning up to gigs wearing weird stuff - superhero costumes, for example.

"Children make a brilliant audience; they're much easier to work with than adults, " says the 32-year-old comic. "Their concentration span is a lot longer and they're sober. I can do more complicated things with children whereas when I do adult gigs, I have to dumb it down."

Campbell bills himself as the only children's stand-up in the world, "perhaps even the entire universe". With that kind of monopoly it's no surprise that he's much in demand. He already has a successful West End run of his Comedy 4 Kids show under his belt and he splits his time between running a comedy club for children in London and performing in schools throughout the country.

There's also the prospect of a TV show in the offing, but he's taking time out from all that to hotfoot it north next month for his fifth Edinburgh festival run.

His act does pretty much what it says on the tin: it's him, a microphone, a glass of water and a set that mixes rehearsed with improvised material. Even with an audience of six-yearolds, fast thinking is often required.

"You can walk out and there'll be a child in the front row in a Spiderman costume. So then you've really got to do a show about Spiderman. It would be rude not to, " he explains. Otherwise, he sticks to subjects that will have some resonance for children. "I talk about schools and parents, why we have hair and what I had for breakfast. Things like that."

Apart from that there's one golden rule - no swearing - and a couple of subjects to steer clear of. Harry Potter is one.

"I've seen a bit of Harry Potter and loathed and despised it. There's nothing on children's television I particularly admire. I'm much more likely to talk about Alien Vs Predator because children watch those sorts of things. They don't tend to be interested in the things that are aimed at them."

Little Britain and Lenny Henry are big favourites among his target audience. He's even met children who can talk about Richard Pryor and Lenny Bruce so he thinks that if it's approached properly, there's little difference between what adults and children find humorous.

"What's funny is funny, " he says. "I think most decent stand-up comedians could do what I do quite easily. It's just a question of remembering to talk to your audience in a way that's relevant to them, and in a way they can understand - which is what you should do with any audience."

Campbell has been performing for children for the last 12 years, but has recently returned to his first love, writing. So as well as appearing in Edinburgh with Comedy 4 Kids, this year he also has a hand in another production: James Campbell's Onomatopoeia Society.

"It's about silly words and shaving hamsters, " he says by way of explaining the plot. "The Onomatopoeia Society exists to promote the use of onomatopoeic words and invent new ones. Its office is in a forest. It's a very silly play, completely insane."

So there you go. Campbell isn't actually in it - he's hired three actors and a director to bring it all together - but don't worry: the humour that has made him the best children's stand-up in the world (perhaps even the universe) is there in bucketloads.

James Campbell's Comedy 4 Kids, The Spiegel Garden, George Square Gardens, August 17-20 & August 27, 4pm (pounds-8). For ages six and up James Campbell's Onomatopoeia Society, Gilded Balloon Teviot, Bristo Square, August 4-28, 2.45pm (pounds-5.50-pounds-9). For ages six and up

HIGHLIGHTS

DR BUNHEAD'S RECIPE FOR DISASTER

The Fringe's favourite mad scientist returns for five performances only, bringing with him his usual battery of booms, bangs, flashes and crashes. It's the sort of pyrotechnic chaos that kids love but Dr Bunhead leavens it with a strong factual content. If only chemistry classes had been this much fun . . .

Aug 24-28, Fringe, The Pleasance, 12.15pm (pounds-7-pounds-9)

JACQUELINE WILSON

With book sales at 20 million and counting, the Tracy Beaker creator has come a long way since her days writing for girls' magazine Jackie in the Dundee offices of DC Thomson. For her services to literacy in schools, Wilson, pictured right, has been awarded an OBE. Four of her books were in the BBC's Big Read top 100 and, in May, she succeeded Michael Morpurgo as Children's Laureate. For her book festival appearance, she'll be reading from new novel Clean Break. If there's a pivotal event for children at the 2005 festival, this is it.

Aug 27, Book Festival, Charlotte Square Gardens, 10am, (pounds-3.50). For ages eight to 11

WHERE SPIRITS AND FAIRIES DWELL

Veterans of children's festivals from Israel to Seattle, Japanese puppet theatre company Kawasemi-za make their Edinburgh debut with a show constructed around Japanese myths and legends. Will they translate? In a sense, they don't need to: Kawasemi-za's use of music and song - not to mention their stunning puppets - is enough to fire any imagination.

Aug 3-13, Fringe, Adam House, Chambers Street, 12.05pm (pounds-8.50-pounds-9.50). Ages six and up

A CLEAN SWEEP

Edinburgh's Dance Base is a modern architectural gem, but the show promises much, too. Inspired in part by Cresser's Brush Shop on the capital's Victoria Street (sadly now defunct), Scottish-based duo Plutot la Vie use clowning as the starting point for this wordless comic turn about Dustin and Walt . . . the keepers of the dust!

Aug 10-20, Fringe, Dance Base, Grassmarket, 10am (pounds-5-pounds-10). Ages six and up

CHARLIE HIGSON

What was James Bond like as a 14-year-old?

Fast Show creator-turned-children's author Charlie Higson thinks he knows and has penned a prequel to Ian Fleming's spy classics.

In SilverFin, planned as the first of a series, young Bond leaves his English boarding school for a summer holiday adventure in the Scottish Highlands.

In this book festival event, Higson will read from the book and answer questions, chief of which should be why he chose to school his Bond at Eton instead of Edinburgh's Fettes College, as Fleming had it.

Aug 13, Book Festival, Charlotte Square Gardens, 3pm (pounds-3.50). For ages 10-13

WALKING THE TIGHTROPE

How do you explain the death of a loved one to a child? That's the question broached by Birmingham Repertory Theatre's youth wing, The Young Rep. Using shadowplay, projections and a script from Mike Kenny, this is the story of Esme - who visits Grandad Stan but can't understand where Nana Queenie has gone.

August 15-20, Fringe, St Columba's by the Castle, Johnston Terrace, 11am (pounds-6.50-pounds-7.50).

Ages three and upwards For bookings, call 0131 226 0000 (Fringe) 0131 624 5050 (Book Festival) or log on to www. edfringe. com or www. edbookfest. co. uk