Having raised two "boys who read," (and three girls as well), I think that the secret here is, like many aspects of "how to," simply lead by example.

Read to your kids when they are very young, let them see you read, make sure that there are plenty of interesting books around, and do your best to instill them with a sense of curiosity. From time to time, drop a book on their bed or desk and say "you might find this one interesting."

Also, my secret policy is to always buy my kids whatever books they ask for, without consideration to price or budget. My younger son (20) almost literally eats advanced math books for breakfast. I am happy to keep him well-fed.

Net-net: Well-informed kids who love to read and a house stuffed with books.