* Historical Fiction: Many of his books are set in historical periods, often with a focus on real events or people. Examples include "The True Confessions of Charlotte Doyle," "Crispin: The Cross of Lead," and "Poppy."
* Adventure Stories: His books often feature exciting plots, adventurous characters, and elements of suspense.
* Fantasy: He has written a few fantasy novels, including "The Fighting Ground" and "The Man Who Was Poe."
* Realistic Fiction: He also writes contemporary stories exploring themes of family, friendship, and coming-of-age.
While these are the primary genres Avi focuses on, his work often blends elements of several, making it difficult to strictly categorize. His stories are known for their depth, historical accuracy, and strong characters, captivating readers of all ages.