If a teacher has ever accused you of wasting your life daydreaming, don't despair: it's worked very well for Australian author Morris Gleitzman. He's written nearly 40 books for children and teenagers, and he dreams up most of his characters and many plots from thin air.
"I've always been a daydreamer - it was my best subject at school," Gleitzman says. "My ideas come from my imagination, my travels, my reading and my hopeful nature."
His stories don't fit into one genre. His first big hit, Two Weeks with the Queen, dealt with sibling rivalry, breaking into Buckingham Palace, and Aids. His Toad series of books, which focus on the importance of environmental protection, is told from the perspective of a cane toad, one of Australia's least loved and most destructive creatures.
Some stories are inspired by more personal - and on the surface, less controversial - interests, such as his latest release Extra Time. This is the story of a teenage football genius, inspired by his childhood love of the beautiful game.
"In my heart I'm still a soccer genius, but my knees don't agree," Gleitzman says, before going on to prove that everything he writes has an important moral. "I'm a lifetime supporter of Charlton Athletic in the UK." Charlton is known for its fluctuating fortunes, or as the author says, "a brilliant team for a writer to support as they remind me every day of the importance of problems in stories".
One of Gleitzman's grandfathers was a Polish Jew, as is Felix, the protagonist of a very successful second world war story so far spanning four books. The first instalment, Once, follows Felix, a six-year-old Jewish boy who escapes from an orphanage. Then followed, which starts when Felix is 10, and Now, where Felix is an elderly man, now living in Australia and looking after his granddaughter.
You might assume the story would come to a natural end once the main character was an old man, but Gleitzman released After in 2012. "Felix, the main character, came back into my imagination with more of his life he wanted me to write about. My characters do this sometimes," he says. "With Felix I was asking for it - at the end of the second book he's 11 and at the start of the third book he's 80, so I'd left quite a big chunk of life that needed writing about. I'm planning two more books in the series."
The Holocaust - the killing of millions of Jewish people by Nazi Germany in the 1930s and 40s - may seem distant and unrelated for teenagers reading his books in Asia. But it's still relevant. Look at the vandalism in February of copies of Anne Frank's diary in Tokyo.
"Hatred and genocide sends all kinds of dark and sad tendrils down through history," Gleitzman says. "Sometimes they wrap around the hearts of individuals or groups, and behaviour results, which dismays us all."
He says it's important to keep teaching about the Holocaust, even if it happened long ago, and may have little relevance for youth today.
"The people who suffered deserve never to be forgotten, and so do the thoughts and actions of all involved," Gleitzman says. "The Holocaust reminds us of the worst we're capable of as a species, and also, sometimes, of the very best. As we navigate our way through life, we need the painful reference points as well as the inspirational ones."
He'll continue to pay tribute to history's heroes with his next book, Loyal Creatures, which is about a 15-year-old boy who volunteers to fight in the first world war with his horse. "Many did just that, and what captured my imagination was that they weren't allowed to bring their horses home after the war."
Gleitzman is vocal about his love of the early 20th-century William stories by Richmal Crompton. "William is a character who breaks all the rules as a result of his good heart," he says. "What more could you ask for in a character than that? Specially when he's very funny.
"Crompton's total respect for her young ragamuffin character is a lesson to all of us writers."
Given Gleitzman's range of stories and characters, it's a lesson that he has taken to heart.