There is a growing awareness that science education should center not just on knowledge acquisition but developing the foundation for lifelong learning. However, for intentional learning of science to occur in school, out of school, and after school, there needs to be a motivation to learn science. Prior research had shown that students'…

Proposes a theoretical model of cognitive development and applies this model to the secondary analysis of two large-scale studies which focus on the acquisition of formal operational schemata by adolescents in the United States and Israel. Results support the "unity" hypothesis of cognitive development that the various schemata of formal…

Examines seventh grade life science students, tenth grade biology students, and college zoology students for understanding of the concept of diffusion. Describes the differences among the grade levels in sound or partial understanding, misconceptions, and no understanding. Discusses the effect of developmental level on understanding. (KR)

Determined that males (N=70) demonstrate higher level of intellectual development than females (N=70), that males mature intellectually earlier than females, and that there appear to be factors other than age and sex that are related to development of formal operational reasoning. Implications of these and other results are discussed. (JN)