Concepts and strategies in children's science experimentation

Most theories treat scientific thinking as a stage of logical development, or a consequence of domain-specific knowledge. In this thesis, it was proposed that experimentation is the result of the development of children's "theory of mind," that is, their understanding of beliefs and the reasons for holding them. Seventy-two children in grades one, three, and five participated in two science experiments, and five tasks which assessed their understanding of causal inference and related concepts.;Children's plans to experiment by contrasting two levels of the independent variable were associated with their understanding of causal inference. Explicit planning, and a distinction between critical and ambiguous evidence, predicted control of variables. Understanding of causal inference predicted changes in beliefs to accommodate discrepant evidence. Understanding of causal evidence predicted the ability to justify a causal or noncausal inference. The results indicated that the same conceptions underpin intrapersonal and interpersonal understanding of causal reasoning, and that these conceptions affect experimentation. Implications for education are discussed.