Investigated the general relationship between children's performance on social and physical measures of cognitive functioning, possible sex differences in performance on the two types of tasks, and the relationship between boys' and girls' performances on these tasks and age and IQ. (SDH)

Two experiments which investigated the young child's ability to deal with multiplicative classes and relations (considered behavioral indices of concrete operations thought) in double series and cross class matrices are described and discussed. In the initial study, 160 children from preschool through grade 2 received six matrix subtasks…

The Conceptual Learning and Development (CLD) Model specifies four levels of concept attainment (concrete, identity, classificatory, and formal) and three uses of concepts (problem solving, subordinate-supraordinate, and principles). Longitudinal and cross-sectional studies of concept attainment may be conducted. The results of this study of 300…