Written for elementary school teachers (and presumably teachers in training), this textbook addresses numbers and operations in the mathematics curriculum of grades K-6 (as well as some topics that may be more appropriate for grades 7 and 8, such as rational numbers, the Euclidean Algorithm, and the conversion of a fraction to a decimal). It contains material intended to aid teachers in answering questions from students, which can frequently require knowledge of the subject beyond the minimal level. The subject is therefore mathematically developed in a comprehensive and systematic manner that reflects the recent emphasis on mathematical coherence as an aid to student learning. Annotation ©2011 Book News, Inc., Portland, OR (booknews.com)