For the age level, this is a rather complete resource book on the atom though too encyclopedic to be called interesting reading. Topics are presented in an expository fashion and grouped in chapters underlining similarity; for example, Chapter Four, ""Molecules and Compounds,"" includes Covalent Bonds, Metallic Bonds and Van Der Waals Bonds, each treated to a paragraph or two. A final, chapter is devoted to mini-biographies of the important figures in the development of atomic concepts. There's a useful glossary and a rather uneven list of suggestions for further reading. In comparison, Asimov's Inside the Atom is less extensive but makes better reading; for a range of readers you will likely want both.