In 1995, gender studies researcher Judy Chu found herself chauffeuring around her 13-year-old brother and his friend. The boys’ curiosity got the better of them, and they asked what she was learning: adolescent girls’ development, she told them.  One of the boys looked at her and said, “‘You should study boys. You can start with me,’” Chu recalled. So she did. That fall, she spoke to 13-year-old boys from home for her clinical interviewing class. In the years since, Chu has researched boys between the ages 12 and 18 — their wishes, their desires, what they wanted from their friendsh...