When seventh graders Felix and Benji find a wallet, they 'borrow' $20 before returning it to its eccentric billionaire owner. Because to a billionaire, $20 is like a penny, right? Not so fast! A penny has real value. When you take a single penny and double it every day for a month, you end up with over $5 million dollars. So the billionaire decides to challenge the boys. Spend $5 million dollars in 30 days. But there are rules: no buying investments (like houses), no buying gifts for people, and they can't tell ANYONE about the challenge. $5 million dollars to do whatever they want? No problem! They boys buy pizza and donuts for their whole middle school every day, fly to Disney World on a private jet, get box seats at a basketball game, and more! But spending money isn't as easy as they thought—especially when they're not even old enough to drive! Stacy McAnulty's third middle grade novel is as smart as it is entertaining and filled with lessons about life, friendship, and what money can and can't buy!