He has dedicated his life to mathematics education and works closely to train teachers at all grade levels. His primary research has focused on problem solving, with publications such as Teaching Problem Solving: What, Why, and How (Dale Seymour), Teaching and Assessing Problem Solving (NCTM), How to Evaluate Progress in Problem Solving (NCTM), and Teaching Mathematics through Problem Solving. Dr. Charles has served as a K–12 mathematics supervisor, Vice President of the National Council of Supervisors of Mathematics, and member of the NCTM Research Advisory Committee. Dr. Charles was also a member of the writing team for the NCTM Curriculum Focal Points (2006). He has authored or coauthored more than 75 mathematics textbooks for the elementary, middle school, secondary, and collegiate levels. Dr. Charles served as the lead author for Scott Foresman - Addison Wesley Mathematics ©2008 and Prentice Hall Mathematics ©2007/2008 and is the lead author for Scott Foresman - Addison Wesley enVisionMATH ©2009.
eBook Prentice Hall Mathematics, Course 2