Karen C. Fuson is a professor emeritus in the School of Education and Social Policy and in the Psychology Department at Northwestern University. After teaching high school mathematics to Chicago inner-city African-American students for 3 years, she began research to ascertain how to help all students enter high school with more knowledge of mathematics. She has conducted extensive research regarding children’s learning of mathematical concepts from ages 2 through 12, focusing in on the development of effective teaching and learning materials, including the “Children’s Math World’s K through 5” curriculum, supporting effective learning for children from various backgrounds, and ambitious accessible learning paths through school mathematics. Fuson was a member of the NRC committee that authored Adding It Up: Helping Children Learn Mathematics.

Sharon Griffin is an associate professor of education and an adjunct associate professor of psychology at Clark University. She is coauthor of “Number Worlds,” a research-based mathematics program for young children, coauthor of What Develops in Emotional Development? (Plenum), and author of several articles on cognitive development and mathematics education. For the past 10 years, she has sought to improve mathematics learning and achievement for young children by developing and evaluating programs to “provide the central conceptual prerequisites for success in school math to children at risk for school failure.” Griffin is currently participating in an advisory capacity on national projects, in Canada and the United States, to enhance the cognitive, mathematical, and language development of “high-need” preschool children, from birth to 5 years.

Mindy Kalchman is an assistant professor in the School of Education at DePaul University. Her research interests include children’s learning of mathematics, theory-based curriculum design, and the effect of discoveries from the field of developmental cognitive psychology on classroom practice. She has coauthored numerous articles regarding mathematics education and curriculum and has conducted workshops on how to teach functions. Kalchman also served as a consulting content editor for the development of the Ontario mathematics curriculum for grades 9–12. She received her Ph.D. from the Ontario Institute for Studies in Education, University of Toronto.

Kenneth R. Koedinger is an associate professor in the Human Computer Interaction Institute and Psychology Department at Carnegie Mellon University. His research interests include cognitive modeling, problem solving and learning, intelligent tutoring systems, and educational technology. Earlier in his career, Koedinger was a teacher in an urban high school. He has developed computer simulations of student thinking that are used to guide the construction of educational materials and are the core of intelligent software