Niagara Falls, or Does It? is the first book in the Hank Zipzer series by Henry Winkler and Lin Oliver, about a creative but learning-challenged fourth-grader who struggles with a summer vacation essay, leading him to build a model of Niagara Falls that floods the classroom instead, getting him into trouble but eventually leading to the discovery of his dyslexia. The book, inspired by Winkler's own childhood experiences, follows Hank as he tries to do the right thing but messes up due to his learning differences, making it relatable for kids who struggle in school.