2 books · Ages 6–10 · Chapter Books
Big Words Biography is a 2-book series for ages 6–10 by Doreen Rappaport. Each book stands alone — start anywhere.
Start anywhere — each book stands alone.
That said, John's Secret Dreams: The Life of John Lennon and To Dare Mighty Things: The Life of Theodore Roosevelt are great first picks.
No particular order needed — browse and pick what catches your eye.