The author of The Illustrated Mum joined poet and broadcaster Michael Rosen to present 20 finalists, each accompanied by a parent and a teacher, with signed copies of books at a special lunch.
Each of the finalists' teachers received pound;100 and their schools pound;200 towards a writer's residency. All visitors also attended an all-female matinee production of Richard III, starring Kathryn Hunter.
Write Away, sponsored by McDonald's and organised with the National Association for the Teaching of English, has been running for six years. It aims to help teachers encourage creative writing while meeting curriculum requirements at key stages 2 and 3.
New autobiographical pieces by writers Terence Blacker, Anthony Horowitz and Geraldine McCaughrean were provided free to TES Teacher, in pages funded by McDonald's, last September. Children aged seven to 14 were then invited to write their own recollections of a significant incident, person or place. This year there were more than 7,000 entries.
The four winning ones, including a witty satire of the competition itself by Alex Gerrald Martin of Studley high school, Warwickshire, are published in today's Friday magazine, and all 20 finalists' entries are on The TES website (www.tes.co.uk).
Jacqueline Wilson said: "I thought the standard was extremely high. It's great that so many children write with such style and flair and heartfelt emotion."