Response to Contradiction: Scientific Reasoning During Adolescence

In this study we examined how students restructure their scientific ideas in response to contradiction. Using equal numbers of male and female subjects, we presented 166 students aged 12, 13, and 14 with two conditions. In one interview condition, students were asked to make predictions about how much water would be displaced by objects of varying size, shape, and weight. They were then asked to test their predictions with physical apparatus by actually immersing objects in water. In the other interview conditions, students were presented with the same experiences, but with an additional early opportunity to examine the equipment and to generate alternative variables. At first, subjects' predictions were generally wrong (in that they were guided by a weight rule). Gradually, most students changed their predictions in the face of contradictory evidence to a correct rule (volume). During the interview, boys learned the correct rule more quickly than did girls. However, there was a significant Sex × Treatment interaction for girls who had the additional opportunity to examine the equipment. We concluded that for girls, such additional experiences may (a) compensate for an initial lack of familiarity with formal experimental settings and (b) encourage them to use analogical reasoning processes to generate a list of potentially relevant variables. Furthermore, we noted that conceptual change requires reflection and that science educators should support the learner's mechanisms for restructuring information.