When Emma Cox returned to school after two days in London, her Year 7 pupils asked her where she had been. The head of English at Exeter Cathedral School replied that it was a secret: she was a bit shy and embarrassed about telling anyone just yet. At this point, a girl called Eleanor raised her hand. “Have you written a book?” she said. “Is it going to be published?”

Ms Cox was astonished. In fact, she had just discovered that she had won the new Children’s Author Prize, organised by the National Literacy Trust and Bloomsbury children’s books. This year’s prize received more than 400 entries. Each entrant paid a £30 fee, raising more than £20,000 for the National Literacy Trust. From those entries, the judges, who included a Bloomsbury editor and a children’s author, picked Ms Cox’s book to be published by Bloomsbury in 2016.

“I asked Eleanor how she knew,” Ms Cox said. “She came and whispered in my ear that she’d written a book, too, and that when I said I was shy and embarrassed, that’s how she feels about her writing, too.”  In fact, Ms Cox has always been intensely private about her writing. “I’ve been writing as long as I can remember,” she said. “Since I was small – like, 4. But I don’t show anyone. You know when you see children at school and they put their arm around their work? I’m a bit like that.”

Despite this, she was persuaded by a friend to enter the Bloomsbury competition. Her novel, Malkin Moonlight, is aimed at children in Years 4 and 5. It tells the story of a community of cats living in a recycling centre. The judges praised its “warmth, humour and strong sense of jeopardy”.

Because Ms Cox works with children from the ages of 6-13, she has a good understanding of which stories and themes engage different age groups. “Children in Year 4 really care about justice and fairness,” she said. “Friendship takes over in Year 5.”

Children’s literature is what she reads for pleasure as well as for work. She has done so “ever since I was a child and was meant to love children’s literature” she said, adding: “Children’s literature is what I love most. I don’t know why.”

Exeter Cathedral is an independent school, which she believes makes it easier for her to make time and mental space for her writing. “Teaching is very demanding,” she said. “You put in the hours.  “But, because you’re teaching a subject you love, every moment you’re doing what you want. I get paid to read stories out loud every day. I do my thing on the whiteboard. And I just talk to children, which is amazing. “So I don’t feel tired. And writing is relaxing – it really is. It’s a nice way to relax at the end of the day.”

Ms Cox has already met her new editor and plans to work on the next draft of the novel over half-term.  “I haven’t come down off my cloud yet,” she said. “I told Year 7 not to tell anybody. By playtime, they’d told everybody. That made it feel more real. Maybe, in about a week’s time, I’ll believe it thoroughly, all the way through.”