Considers what college students think reasoning about physics involves. Discusses whether it is possible to identify students' general conceptions of physics and the effects of a course on students' concepts. Data indicated that students' understandings had an effect on problem solving, qualitative problems, and misconceptions. (YP)

Reports the rationale, design, validation, and uses of the "Force Concept Inventory," an instrument to assess the students' beliefs on force. Includes results and implications of two studies that compared the inventory with the "Mechanics Baseline." Includes a copy of the instrument. (MDH)