A longitudinal study was conducted to identify unique sources of individual differences in later understanding of the equal sign as a relational symbol of equivalence (i.e., formal understanding of mathematical equivalence). The sample included 141 children from a mid-sized city in the Midwestern United States (M[subscript age] = 6 years, 2 months…

Elementary school students often lack a conceptual understanding of linear measurement, which is revealed by their poor performance when the object to be measured is not aligned with the start of the ruler. Instead of correctly counting the units that correspond to the object (e.g., inches or centimeters), children often use 1 of 2 incorrect…

Teacher-child relationships have been linked to children's classroom engagement and to academic achievement. However, researchers have paid minimal attention to individual child factors that predict the development of these relationships. In the current study, we examined executive function (EF) prior to school entry as a predictor of…

This article examined the ability of young children to adapt their trust in testimony in relation to the strength of their prior knowledge across 2 cultures and 2 age groups. Kindergartners and second graders in the United States and Hong Kong (N = 128) viewed pictures of objects and made category judgments about each object: first, in the…

We studied developmental trends in 5 important reasoning tasks that are critical components of the operational definition of rational thinking. The tasks measured denominator neglect, belief bias, base rate sensitivity, resistance to framing, and the tendency toward otherside thinking. In addition to age, we examined 2 other individual difference…