CK-12 Foundation is a non-profit organization with a mission to reduce the cost of textbook materials for the K-12 market both in the U.S. and worldwide. Using an open-content, web-based collaborative model termed the "FlexBook," CK-12 intends to pioneer the generation and distribution of high quality educational content that will serve both as core text as well as provide an adaptive environment for learning through the FlexBook Platform™.
A good supplement to a traditional history book - with original documents and reprints or news articles, political cartoons and other contemporary pieces along with questions for interpretation and analysis. A good read in and of itself, and a potent resource alongside traditional history books in the classroom.
It was pretty basic. It was a good OUTLINE for history. But clearly just an OUTLINE. It does say in the beginning that it's just a source book and you cannot use it as a full curriculum which is good. Even so, I wouldn't read this book unless you just want to know the basic or where to start when studying history.