"Does it really fly?" I looked up. I was packing away the big box of dressing-up clothes I bring with me when telling stories in junior schools - all around the classroom children were reluctantly taking off the colourful cloaks, satin dresses, embroidered waistcoats, crowns and necklaces in which they'd listened to my stories.
One of today's stories involved a magic carpet, so I'd also brought along a small Indian rug, which I'd unrolled at the right moment, to let the children sit on it. Now, a small boy of seven was poking it respectfully with his toe and looking up at me with big eyes: "Does it really fly?"
Children don't get so much magic in their lives that you can afford to let them down. I was moved that he had listened to the story with such conviction. "I don't think so," I told him. "I've never seen it do anything unusual. But you never know!" At which he nodded, apparently satisfied. It had clearly been a magic carpet to him.
I began storytelling several years ago in France, with a group of volunteers, English and American mothers who wanted an English-language story session for children aged three to seven. We decided that instead of reading aloud from picture books and story books, we would try telling stories "from the heart", in the oral tradition.
Some found it too stressful - one expectant mother hastily gave up after experiencing contractions - but others, myself included, loved the immediacy, the eye contact, the direct relationship between storyteller and listeners. Books, pictures, other people's words - no need for them! If you know a story, and you love it, you can tell it again. It's as simple as that.
One great practical advantage of telling stories from the heart is that it leaves your hands free. You are not holding a book, so you can use hands and face and body to tell the story. It's a much more lively performance than sitting, looking down and reading aloud. And written English is nearly always more formal, more stiff, than a story you retell and remake in your own voice.
Young children have short attention spans. For Years 1 and 2 it's best to choose stories with a simple plot and plenty of repetition, preferably with some kind of chorus they can join in. If they're having fun chanting in unison, or making animal noises, they're engaged with the story and less likely to be finding something interesting on the floor or playing with their friend's hair.
In one such story, "How the Manx Cat Lost Her Tail" (trapped in the door of Noah's Ark), the children join in, calling "Kitty, kitty, kitty, kitty!" to help Father Noah call the lost cat home before the rain starts to fall.
Years 3 and 4 will listen to more complicated stories, and follow a twisting plot quite easily. They appreciate humour, and they like scary stories. If I can bring in props, I will. There are lots of comical folk-stories about the Devil being worsted, which I like to tell around Halloween: one involves the clever wife of a farmer who manages to save her man by getting the Devil to bite into a pie in which she has hidden a red-hot griddle. I always take a cast-iron griddle into the class and hand it round before I begin, getting the children to feel the weight and guess what it is. This gets them involved: they understand what's happening, and can appreciate the trick.
Years 5 and 6 are in some ways my favourite age-group. They can concentrate on quite complicated stories and are sophisticated and rewarding listeners.
One or two children may feel a bit too grown-up for "fairy tales". The trick is to begin with a bang, by telling them one of the stronger of the Grimms' Fairy Tales - of which there are many.
An English story that never fails is "Mr Fox", a version of "Bluebeard".
It's gruesome, hypnotic, the heroine has attitude, and the ending is entirely satisfactory as she turns the tables on the evil Mr Fox. I've been thrilled to have children come up to me a year later, asking to hear it again. "I told it to my mum," said one. "I told it to my friend," said another.
Give children the impression, right from the start, that they are going to have fun. My dressing-up box, collections of bright, exotic clothes and fabrics garnered from Oxfam shops over the years, has been invaluable. At first I brought it only for the younger age groups, but I soon realised everyone wants to dress up. It's amazing what a child's imagination can do with an off-cut of sari material. And setting free the imagination is what storytelling is all about. It's wonderful, because it's so democratic.
Every child in the class can join in, and it doesn't matter if they're good or bad readers. They are all equally good at making pictures in their heads.
* Katherine Langris's debut novel, Troll Fell, for eight to 12-year-olds, has just been published (Harper Collins Children's Books, pound;9.99)