This is a unit for the novel Dolphin Adventure by Wayne Grover. This is a nonfiction book and excellent for grades 3-6. There are questions for each chapter. There is also a study guide that could be used in a literature center. I have also included a page on figurative language. Dolphin Adventure has many similes, metaphors, and hyperboles.
If you need a nonfiction novel, your students will really enjoy this one!