THIS 1948 LECTURE ON THE SOCIALIZATION AND MENTAL ACTIVITIES OF NEGRO AND WHITE MIDDLE- AND LOWER-CLASS CHILDREN DISCUSSES (1) THE STRUCTURE OF REWARDS AND PUNISHMENTS AMONG MIDDLE- AND LOWER-CLASS PERSONS, (2) THE INFLUENCE OF SOCIAL CLASS ON PROBLEM SOLVING IN STANDARDIZED MENTAL TESTS, (3) THE NATURE OF PROBLEM-SOLVING ACTIVITIES AND MENTAL BEHAVIOR, (4) CULTURAL BIAS IN STANDARDIZED MENTAL TESTS, (5) THE INADEQUACY OF CURRICULUMS FOR OPTIMAL MENTAL DEVELOPMENT AND THE MIDDLE-CLASS ORIENTATION OF THE SCHOOL CULTURE. SOCIAL CLASS IS SEEN AS A "SYSTEM OF PRIVILEGE" WHICH LIMITS AND RIGIDLY DEFINES THE LEARNING ENVIRONMENT, AND THE PUBLIC SCHOOLS, WHICH MIGHT PROVIDE AN ENVIRONMENT WHERE LOWER-CLASS CHILDREN CAN LEARN MIDDLE-CLASS VALUES AND MOTIVATIONS, AS FAILING IN THEIR SOCIALIZATION TASK. IT IS ALSO FELT THAT MIDDLE-CLASS CHILDREN, WHO ARE GENERALLY TRAINED IN A LESS PERMISSIVE MANNER THAN ARE LOWER-CLASS CHILDREN, MAY BE EMOTIONALLY BRUISED BY THEIR PARENTS' EARLY DEMAND FOR ACHIEVEMENT. ALSO DISCUSSED IS A RESEARCH PROJECT TO CONSTRUCT CULTURE-FREE TEST ITEMS WHICH WOULD MEASURE A BROAD-RANGE OF MENTAL ACTIVITIES. THIS DOCUMENT IS AVAILABLE FROM HARVARD UNIVERSITY PRESS, CAMBRIDGE, MASSACHUSETTS. (LB)