Growing out of a child's cognitive developmental history, formal operation becomes established at about the age of 12-15 years. The essence of the logic of cultured adults and the basis for elementary scientific thought are thereby provided. The rate at which a child progresses through the developmental succession may vary, especially from one…

Adolescents often pursue learning opportunities both in and outside school once they become interested in a topic. In this paper, a learning ecology framework and an associated empirical research agenda are described. This framework highlights the need to better understand how learning outside school relates to learning within schools or other…

Five symposium papers evaluate the usefulness of ideas associated with the life-span view for enriching, highlighting, or expanding issues, theory, and research pertinent to change processes during infancy, childhood, adolescence, and adulthood, and for intervention programs during these periods. (Author/MP)