Mr Strong's book, The Hundred Mile-An-Hour Dog, was chosen from nearly 900 entries, pipping writers such as Terry Prachett and Gillian Cross.
Previous winners, chosen each year by children from schools and book clubs across the country, include Roald Dahl and Terry Jones.
"For me this is the best kind of award to win," said Mr Strong, 47, who has more than 40 children's titles to his name. "It is an honour to be chosen by those who actually read the book."
The book is the story of a young boy, who offers to look after the hundred- mile-an-hour dog, Streaker, with disastrous consequences. "The characters in the book are an amalgam of people and animals I know," said Mr Strong. "The trick to writing for children is to make a book exciting yet within the bounds of credibility."
He retired from teaching five years ago but still visits schools regularly."I was brought up on the Beano, mainly because my parents banned comics. I think it's healthy to be somewhat child-like in your thinking."Reuse content