The money book that plays like a game: £1 doubles every page. Ages 8–12.How many doubles does it take to turn £1 into £1,000,000?Go on — guess. Write it down. Most grown-ups get it spectacularly wrong, and finding out the real answer is the first page of this book.The Double-Up Challenge is a money book for readers aged 8–12 that works like a game. Your pound doubles every single time you turn the page: 21 chapters, one page each, from a coin found down the back of the sofa to the million-pound page. Along the way you'll meet Sid (likes to spend) and Sage (likes to save), and watch their summer dog-walking race end in a genuine photo finish — one you can check with a pencil.Inside: The guess page — write your answer down before the book reveals the truth Sid and Sage's dog-walking race, with a fill-it-in counting table that lets the reader discover the winner themselves Why a certain chocolate frog keeps getting dearer (inflation, but funnier) The oak tree's secret: branches grow branches The money machine, the treasure chest, the temptation test — and the one golden rule Sage's three little games for beating temptation: the Sleep Test, the Swap, and the First Pound Every sum in this book can be checked by a ten-year-old with a pencil. That's a promise. No jargon, no lectures, and no pretending money is boring. Just the most useful idea a young person can learn — that small choices, repeated patiently, grow into something enormous — hidden inside a game they'll actually want to finish.What you get: a beautifully designed PDF edition, laid out page-for-page as the printed book, ready to read on a tablet or print at home. Read it together, or hand it over and wait for them to come and tell you the answer.Perfect for curious kids, patient parents, generous grandparents, and any teacher who's ever tried to explain compound growth before lunch.Paperback edition coming to Amazon. Play the challenge and share your family's guesses at howmanydoubles.com — #HowManyDoubles