Grade 4-6-Designed as brief overviews of very broad topics, these volumes describe each subtopic in one to three paragraphs. The frequent references to the end of the millennium are irritating and imply that time has ended, and the introduction to Weapons gives the impression that all weapons existed only in this past 1000-year period. The text then reverts to a discussion of the Stone Age. Weapons, in particular, tends to make some sweeping general statements that could be considered unsubstantiated. The books have plenty of white space with numerous, captioned photos and illustrations, but too often the pictures are too small to be effective. Vocabulary is appropriately technical, but unfamiliar terms are not defined in context. Both titles conclude with a time line of the last 1000 years.
