I just finished Lies My Teacher Told Me by James W. Loewen. The author examined a dozen high school American history textbooks, and he details how well (and, more often, how badly) they present the subject. It's quite an interesting book; some of the things in there may surprise you (they surprised me, and I thought I had an excellent American history course in high school).
In addition to the Bill Bryson books mentioned above, I'd also recommend his The Mother Tongue: English and How It Got That Way.
In addition to the Bill Bryson books mentioned above, I'd also recommend his The Mother Tongue: English and How It Got That Way.