TheFifth EditionofMathematical Reasoning for Elementary Teachers,with new co-author Richard Millman, focuses on mathematical knowledge needed for teaching–demonstratingwhyfuture teachers are learning math content as well aswhenthey will use it in the classroom. One of the most important aspects of teaching is being able to explain why students’ methods and ideas are either right or wrong. Imparting this skill to future teachers the emphasis of this fantastic text.