However, boys read fiction too!
It doesn't really matter to me whether a boy is choosing to read nonfiction rather than fiction, but I love it when he discovers a fictional series that he just can't put down. Sometimes that's the secret. When boys find a series that's right for them, they know their next check-out is an easy choice, because it's the next book in the series. They are betting, and usually correctly, that if they loved one, they are going to love them all.