Mo Willems, creator of the revolutionary, award-winning, best-selling Elephant & Piggie books, is back with another breakout beginning-reader series. An ensemble cast of Squirrels, Acorns, and pop-in guests host a page-turning extravaganza. Each book features a funny, furry adventure AND bonus jokes, quirky quizzes, nutty facts, and so, so many Squirrels.In I Lost My Tooth!, Zoom Squirrel has lost a front tooth! The Squirrels leap into action when they discover the missing tooth is a baby tooth! Do you know more about teeth than the Squirrels do? You will by the end of this book!