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…

Interview data exemplify students' attempts to integrate the concepts of electrochemistry with related knowledge that they had previously constructed or acquired in other classes. The implications for minimizing potential misconceptions center on the difficulties students experience when using more than one model for explaining scientific…

Presented is a criticism of Lawson's (1988) article on the development of misconceptions of biological concepts. Lawson's response to this criticism follows. (CW)

Examines 11 elementary science texts in terms of conceptual structure and reasoning demands using concept maps. Reports that (1) the conceptual structures vary widely across texts; (2) most of the structures are well defined; and (3) the reasoning demands are above the developmental capabilities of most of primary-level children. (Author/YP)

More than 1,600 middle school students, including an experimental group exposed to the Biological Science Curriculum Study (BSCS), were administered the Modified Nature of Scientific Knowledge Scale. Results indicate that the students utilizing the traditional science curriculum possessed a significantly better understanding of the testable nature…