HDE 100A - Infancy and Early Childhood Biological, social, and cultural influences in the psychological growth and development of children, prenatal through age six. Two observations of preschool children required. HDE 100B - Middle Childhood and Adolescence Interplay of biological and social-cultural factors in the emotional, cognitive and social development from middle childhood through adolescence. You must take BOTH of these courses to satisfy the Educational Psychology prerequisite.