The purpose of this study involving 12 classrooms was twofold: (1) to understand the conceptual frameworks that sixth-grade students use to explain the nature of matter and molecules, and (2) to assess the effectiveness of 2 alternative curriculum units in promoting students' scientific understanding. Results reveal that students' entering…

Beginning physics students (n=42) were constrained to analyze mechanics problems according to a hierarchical scheme that integrated concepts, principles, and procedures. After five one-hour sessions, students increased their reliance on the use of principles in categorizing problems according to similarity of solution and in writing qualitative…

Changing ideas about the origin of the Silurian Clinton oolitic ironstones in eastern United States provide an instructive example of how interpretations develop as knowledge increases. (PR)

Describes a course, "Great Ideas in Science," for undergraduate nonscience major students. The course emphasizes a few key overarching concepts in physics, chemistry, geology, and biology to introduce students to the essential aspects of science without getting involved in the complex vocabulary or rigorous mathematical derivations. (PR)

The principles of magma addition and liquid layering in magma chambers can be demonstrated by dissolving colored crystals. The concepts of density stratification and apparent lack of mixing of miscible liquids is convincingly illustrated with hydrous solutions at room temperature. The behavior of interstitial liquids in "cumulus" piles…

Discusses three teachers' syntactical subject matter knowledge in science. The focus of the discussion is the link between teachers' views of the growth of scientific knowledge and the methods they use to help students construct a knowledge of science. (IAH)

Based on the premise that body experiences interfere inconveniently with scientific ideas in mechanics instruction. Suggests that learning processes start with body experiences and, with guidance, transform them into something scientific. Discusses this process for the static and kinetic aspects of force and for measurement. (MDH)

The ways in which the concept of acceleration is treated in physics textbooks is compared with understandings of the concept demonstrated by final-year secondary (n=30) and first-year university students (n=60). Some students' understanding are shown to be incomplete in ways that parallel misleading or inaccurate textbook treatment of the concept.…

Describes the preparation and importance of a project where junior high school students stenciled "No Dumping! Flows to the Bay!" on storm drains in the area of their school. (PR)

Presents and discusses a contract to encourage students to get involved in cleaning up the environment. (PR)

Provides a student worksheet and set-up instructions for a science experiment to demonstrate the concept of density. Students are asked to explain the phenomenon in which a liquid of lower density placed in the bottom of two vertical flasks flows up to replace the liquid of higher density in the upper flask. (MDH)

Describes an activity where students find the locations and elevations of their homes, school, favorite parks and lakes, and other significant places as they learn topographic skills and unique features of the community. (PR)

Presents an activity to help students understand the precepts of the Hardy-Weinberg principle and simultaneously permit observation of a model of evolution through natural selection in a nonthreatening setting. (PR)

Raises questions regarding what students are perceiving when concrete models are used to represent abstract scientific concepts. Discussion of several exploratory investigations on the role of models in science teaching is presented in three areas: (1) interactions with students; (2) effectiveness of models; and (3) spatial ability and models.…

Describes combining the simple activity of collecting monthly student height measurements with the technology of using a computer spreadsheet for a year-long activity that teaches measurement and data manipulation. (PR)