10 Who HQ Books (Who? What? Where?): What Were the Twin Towers, Pearl Harbor, Hurricane Katrina, D-Day, the Hindenburg, the Age of the Dinosaurs, and the Wild West. Penguin Workshop, 2013-2017, about 100 pages each. Ages 7-10 years. Paperbacks in excellent condition. Text only. Cash or Venmo. Discount on multiple items.