This book one of my ultimate childhood favorites! This book could be used in grades 1 - 3. In the book, Miss Nelson's class is misbehaving and she comes up with an idea on how to get her students to behave the appropriately. The next day, the students come in the classroom to find Miss Viola Swamp. Miss, Swamp is the meanest substitute teacher the students could ever imagine. By the end of the day, Miss Swamp has the students behaving appropriately. There is a secret to where Miss Nelson is, but to find out you have to read the book! I would read this book at the beginning of the year so the students know that if they do not listen to their teacher, there could potentially be someone a lot worse to come in. This book is at a lexile level of 340L.