Math Expressions author, Dr. Karen Fuson, is Professor Emerita of Learning Sciences for the School of Education and Social Policy, as well as the Department of Psychology, at Northwestern University. Dr. Fuson’s research is highly regarded in the field of elementary mathematics for her involvement in the Common Core and the Common Core Learning Progressions and for spearheading the Children’s Math Worlds (CMW) Research Project—a 10-year study of how to effectively teach students math from an early age. The CMW Research Project examined how teachers can build conceptual supports, including meaningful language, drawings, manipulatives, and classroom communication methods, to facilitate mathematical competence. The results from this research helped create Math Expressions.