Scientific reasoning in elementary school age. The ability to test hypotheses and evaluate evidence about the causes of achievement outcomes

In the present study, we explore the development of scientific reasoning in elementary school age, using the domain of hypotheses about the causes of achievement outcomes. Children's metaconceptual understanding of the hypothesis-evidence relation was assessed with four measures: (1) Subjects' suggestions for testing their own attributional hypotheses, (2) their choice of relevant test strategies, (3) the ability to specify hypothetical sets of expected and unexpected outcomes, given a certain hypothesis, and (4) the ability to give valid evidence-based justifications for causal inferences from covariation data. The majority of the fourth-graders, but only few second graders, and almost all adults consistently showed a metaconceptual understanding of the hypothesis-evidence relation. The findings indicate developmental progress during elementary school age. They are consistent with the findings of the few studies addressing the beginnings of scientific reasoning in grade schoolchildren that have been conducted to date. The choice of a knowledge-rich domain in our study did not provide evidence for early metaconceptual understanding. However, knowledge-rich domains offer a new outlook on evaluating the "child as scientist" metaphor.