Sex difference research has been plagued with a myriad of problems,. Specifically, intelligence testing, if dependent on measurement of spatial or verbal proficiency, may not be an accurate indicator of native ability. Similarly, infrequent replication of studies, studies that only include subjects of one sex yet imply sex differences, and poor…

This study is an attempt to identify social interactions which fit into a Piagetian model for cognitive change, and specifically to examine the degree to which the frequency of those interactions predicts the rate of cognitive development. The subjects were 74 elementary school children enrolled in 19 K-4 classrooms. These children were in the…

This study focuses on the effects of family size and spacing on intellectual, social, and personality development of children. The sample consisted of 533 suburban, middle class, large family (five or more) and small two child family children. The children, 233 boys and 300 girls, were teenagers attending either junior or senior high school.…