"A laugh-out-loud tour de force." -- Kirkus , starred review Hidden away at Hopewell Elementary School is a magical locker that always delivers a solution to your problems--just not quite in the way you might expect. This highly illustrated series is a fun and accessible read, perfect for reluctant readers looking for a little magic! In the third book in the series, Locker 37 at Hopewell Elementary has been helping fourth graders solve their problems for as long as anyone can remember. So when Riley Zimmerman needs help pulling off the most ridiculous and wonderful prank the school has ever seen, the magical Locker 37 provides her with an equally ridiculous and wonderful rainbow hat that can clone anything that wears it. But will a group of clones, an untrustworthy bully, and 10,000 Ping-Pong balls be enough to help Riley pull off the most legendary prank in Hopewell's history? Aaron Starmer was born in northern California and raised in the suburbs of Syracuse, New York. Before pursuing writing full-time, he worked in New York City for over ten years as an editor for a travel bookseller and as an operations director for an African safari company. His middle grade and young adult novels have been translated into multiple languages and have appeared on best of the year lists from Time magazine, the Wall Street Journal , New York Public Library, YALSA, Bank Street College of Education, Chicago Public Library, and School Library Journal. His latest novel, Spontaneous , is in development as a film. He lives in Vermont with his wife and two daughters. Chapter One Predictability    “You’re predictable.” The words burned in Riley Zimmerman’s mind. Her best friend, Carson Cooper, had said those words to her a week before, and she had been thinking about them constantly. Because they were wrong. Riley Zimmerman was not predictable. She was sure of it. Because predictable people aren’t unique. And if Riley Zimmerman was one thing, she was unique. Not very unique, or a little unique, because that’s not possible. The word unique doesn’t play well with adverbs. Unique means one of a kind, and a person can’t be very one of a kind or a little one of a kind. They can be unique. Full stop. And that’s exactly what Riley was. There was no one else like her. Which, for Hopewell Elementary, was a good thing. That school wouldn’t have lasted a week with more than one Riley roaming its halls. After all, it barely lasted a day when—­ Well, we’re getting to that. First, let’s start with Ping-­Pong balls. Riley had ten thousand of them. And she was going to use them to prove Carson wrong. She lived within walking distance of the school and arrived early one autumn morning. Before the first bell rang, Riley hurried back and forth from her house to the school, dragging ten bumpy trash bags filled with a thousand Ping-­Pong balls each. She set the bumpy trash bags against the back wall of the school, where there used to be a dumpster, and she waited for the janitor, Reggie Blue, to unlock the rear exit. This was part of Reggie’s morning routine, something Riley knew because she had recently become a member of the Junior Janitor Club. She now had access to secret knowledge. When she heard the click of the lock, she counted to one hundred so she could be confident the coast was clear. She took a deep breath. Then she smuggled the bags down to the basement of Hopewell Elementary and into the Dungeon. Chapter Two Best Friends Yes, Hopewell Elementary had a Dungeon. It’s not what you think. Or maybe it is what you think. If you’ve heard of Hopewell Elementary, then you’ve heard of the Dungeon. It was a bathroom that was super old and super gross and full of spiderwebs and creaky sounds, and no one actually used it for standard bathroom purposes. It was mostly a place for fourth-­graders to find privacy, or to talk about Locker 37. If you’ve heard of Hopewell Elementary, then you’ve definitely heard of Locker 37. It was a magical locker that provided solutions to fourth-­graders’ problems. It’s not an exaggeration to say that Locker 37 was the universe’s most wondrous creation. We’re getting to Locker 37, too. For now, let’s focus on the Dungeon: an awful bathroom, but an excellent hiding place. Also, the ideal location to feed Ping-­Pong balls into the school’s heating ducts. That’s exactly what Riley was doing on that chilly morning before homeroom. She had opened a vent on a wall in the corner and was pouring the bags of Ping-­Pong balls in. This was not something Riley did every day, of course. She was a master of mischief, but she had never attempted anything so ambitious. Or risky. If she were caught, it would mean a swift and significant punishment. But here’s the thing: Riley could always think or talk her way out of a jam. Even she would admit she was predictable in one way. She never got caught. Until . . . “What the heck are you doing?” a voice said. Riley swung around and sp