A fundamental question in numerical development concerns the directional relation between an early-emerging non-verbal approximate number system (ANS) and culturally acquired verbal number and mathematics knowledge. Using path models on longitudinal data collected in preschool children (M[subscript age] = 3.86 years; N = 216; 99 males; 80.8%…

Algebraic competence is a major determinant of college access and career prospects, and equal sign knowledge is taken to be foundational to algebra knowledge. However, few studies have documented a causal effect of early equal sign knowledge on later algebra skill. This study assessed whether second-grade students' equal sign knowledge…

During communication, conversational partners should offer as much information as is required and relevant. For instance, the statement "Some Xs Y" is infelicitous if one knows that all Xs Y. Do children understand the link between speaker knowledge and utterance strength? In Experiment 1, 5-year-olds (N = 32) but not 4-year-olds…

Early mathematics knowledge is a strong predictor of later academic achievement, but children from low-income families enter school with weak mathematics knowledge. An early math trajectories model is proposed and evaluated within a longitudinal study of 517 low-income American children from ages 4 to 11. This model includes a broad range of math…

Despite research demonstrating a strong association between early and later mathematics achievement, few studies have investigated mediators of this association. Using longitudinal data (n = 1,362), this study tested the extent to which mathematics self-concepts, school placement, executive functioning, and proficiency in fractions and division…

Do young children appreciate the importance of access to premises when judging what another person knows? In Experiment 1, 5-year-olds (N=31) were sensitive to another person's access to premises when predicting that person's ability to point to a target after eliminating alternatives in a set of 3 cartoon characters. Experiment 2 replicated the…

Examined toddlers' awareness of partners' knowledge states when communicating with them. In two studies, the parent either witnessed or did not witness placement of an object the child asked for help in retrieving. Subjects named the object and location and gestured to its location more often for parents who did not know the information than for…

Factors affecting performance on base-10 tasks were investigated in a series of four studies with a total of 453 children aged 5-7 years. Training in counting-on was found to enhance child performance on base-10 tasks (Studies 2, 3, and 4), while prior knowledge of counting-on (Study 1), trading (Studies 1 and 3), and partitioning (Studies 1 and…

Studies conducted among the Kpelle of north central Liberia whose present cultural milieu offers unique possibilities for studying the role of particular experiential factors, particularly education, on the development of paradigmatic response. (Authors)

This study examined relations among cortisol reactivity and measures of cognitive function and social behavior in 4- to 5-year-old children (N=169) attending Head Start. Saliva samples for the assay of cortisol were collected at the beginning, middle, and end of an approximately 45-min testing session. Moderate increase in cortisol followed by…

Three studies used interspecies adoption stories to examine children's understanding of the role of birth in determining animal properties and species identity. Found that most 4- to 7-year olds could reliably judge that babies would be of the same species as birth parents, but were unable to attribute properties of adoptive parents. (Author/KB)

Outlines new directions for research on parents' contributions to children's values. Advocates research that demonstrates that parental understanding of a particular child's characteristics and situation is the mark of effective parenting, traces differential impact of varieties of parent responsiveness, assesses conditions surrounding the fact…