FACILITATING CONCEPTUAL CHANGE USING ANALOGIES AND EXPLANATORY MODELS

Learning in the sciences is increasingly viewed as a process of conceptual change rather than simply conceptual growth. Recent research indicates that the use of 'bridging' analogies can be effective in facilitating conceptual change. These bridging analogies are conceptually intermediate between situations drawing out valid 'anchoring' intuitions (e.g., that springs can exert forces when compressed) and target problems drawing out naive conceptions (e.g., that a table cannot exert an upward force on a book resting on the table). For example, a sequence of bridging analogies from a hand pressing on a spring, to a book resting on a flexible table, to a book resting on a solid table can help the student make sense of the upward force from the table. In this study, 40 high school students who indicated the table would not exert an upward force interacted with a written, bridging explanation. Students responded in writing to questions embedded throughout the explanation. Analyses of these written responses support the following hypotheses raised in earlier interviewing studies: (1) analogies which might seem appropriate to the scientist may not appear so to the student, who would thus reject the analogy relation; (2) in such cases, bridging analogies may be necessary in order to establish analogical relationships; and (3) these analogies may need to help students construct an explanatory model in order to aid learning (in this case, the model of a table as springy on a microscopic scale). This previously unrecognized microscopic springiness can help the student make sense of the idea that the solid table can exert an upward force by helping the student focus on previously hidden mechanisms operating in the target situation.