When you think about your favorite teacher, you probably don’t remember what grades they gave you—you remember how they made you feel. Maybe they got you excited about a book or a science experiment, showed you care during a hard time, or gave you a piece of advice that stuck. A new book from Isabelle Hau, executive director of the Stanford Accelerator for Learning, explores the science behind why relationships are key to learning and development, from the early years through adulthood. I...