The interaction of domain-specific knowledge and domain-general discovery strategies: a study with sinking objects.

Recent work on scientific reasoning has largely focused on either domain-specific content knowledge or domain-general reasoning knowledge. This study investigated the interaction between the 2 types of knowledge in a real-world domain in which strict control of variables was not possible. We used a context, sinking objects, in which 10-, 12-, and, 14-year-old children's strong a priori beliefs could be revealed by participant-designed experiments. The results showed that most children initially believed weight alone determined an object's sinking rate. Older, but not younger, participants typically viewed experimentation as a means of exploring the effects of attributes other than weight. However, experimentation did help all children to understand the effects of object shape and material on sinking rates. The results suggests a number of questions for further research, including how children come to understand experimentation as a matter of evaluation rather than demonstration, and the role of unexpected experimental results in driving conceptual understanding.