This volume of the Handbook of Psychology is dedicated to the field of educational psychology. Educational psychology is focused largely on the application of psychological principles to the study of human learning and development in educational settings. Educational psychology traces its roots to the beginnings of psychology as a field of study in the United States with the pioneering work of William James. Research in the field of educational psychology has progressed over the past century with an explosion of research across numerous domains of this field in the last quarter of the twentieth century.