To contribute to a more differentiated description of the cognitive status of young disadvantaged children, a comparative study was made of achievement test performance of disadvantaged and middle class groups of children. On the basis of published reading test scores, test data were gathered from nine public schools, four of which were selected…

IN 1960 AT TORONTO, CANADA, A LONGITUDINAL STUDY OF ACHIEVEMENT WAS BEGUN IN JUNIOR KINDERGARTEN WITH 8,695 CHILDREN. THE OBJECTIVES OF THE STUDY WERE (1) TO EVALUATE THE EFFECT OF JUNIOR KINDERGARTEN ATTENDANCE ON THE ACHIEVEMENT AND DEVELOPMENT OF CHILDREN, AND (2) TO EXAMINE THE NATURE OF THE WORLD OF JUNIOR AND SENIOR KINDERGARTEN CHILDREN.…