We examined differences among children in their endorsement of an adult's claim, their subsequent empirical investigation of that claim, and their resolution of any potential conflict between the claim and their empirical investigation. American and Chinese preschool (N = 171, M = 4.71 years) and elementary school (N = 128, M = 7.59 years)…

This study investigated effects of feedback and exposure to alternative strategies on strategy change in children (N = 106, age range = 7;3-10;0) learning about mathematical equivalence. Children's strategies were evaluated before and after a brief instructional intervention. During the intervention, children either were exposed to a set of 4…

The principle of "inversion," that a + b - b "must" equal a, is a fundamental property of arithmetic, but many children fail to apply it in symbolic contexts through 10 years of age. We explore three hypotheses relating to the use of inversion that stem from a model proposed by Siegler and Araya (2005). Hypothesis 1 is that…

Data collection can be the most time- and cost-intensive part of developmental research. This article describes some long-proposed but little-used research designs that have the potential to maximize data quality (reliability and validity) while minimizing research cost. In "planned missing data designs", missing data are used…