I've discussed the book to some extent here, but if you have any more specific inquiries I'd be glad to help. As I note there, his coverage of the colonization of the Americas is questionable at best, a flagrant display of terrible historical practice at worst. Teaching What Really Happened, Loewen's follow-up, is a somewhat better handbook for teaching history, though it retains his other books emphasis on "true" history, as evidenced in the title itself. It's still worth a read if you take that into consideration. The book I mention in the linked post, Disciplinary Literacy, is one of the most helpful education textbooks I've read, and though it could spend more time on the social studies I would encourage you to pick it up.