This is a wonderful book. We bought it recently after hearing Michael Morpurgo talk in England to 600 adults and children and keep each and every one rivetted for half an hour, even the five year olds.
Both our 14 year old son and 8 year old daughter adored it. Our son says he loved the way it explains how you turn an idea into a story and illustrates examples with real and autobiographical tales. It's rare that a book appeals as much to an eight year old, a fourteen year old and adults.
They also loved many of his other books, and our daughter has recently read Butterfly Lion, Wreck of the Zanzibar and Cool and loved them too.