Free to Learn

If you read only one book on the importance of alternative schools, unschooling, or homeschooling, make it this one. If you have children, read this book.

It's easy to read, well organized and written, and very approachable, even if you don't have a strong interest in the topic (although, by the end, you might).

Quick note: I was surprised to see that he never mentioned the difference in kids personalities in regard to learning style, although it is slightly off topic. I believe different kids need a different style of parenting, and that should factor in to their education (a “free spirit” needing a bit more structure than a more organized child, for example). In the end it's like anything else - you have to do what works for you and your family, which usually involves a mashup of several different styles or systems.