Recent work has probed the developmental mechanisms that promote fair sharing. This work investigated 2.5- to 5.5-year-olds' (N = 316; 52% female; 79% White; data collected 2016-2018) sharing behavior in relation to three cognitive correlates: number knowledge, working memory, and cognitive control. In contrast to working memory and cognitive…

Educators often use concrete objects to help children understand mathematics concepts. However, findings on the effectiveness of concrete objects are mixed. The present study examined how two factors--perceptual richness and established knowledge of the objects--combine to influence children's counting performance. In two experiments, preschoolers…

In two studies of knowledge about the properties and processes of memory for the times of past events, 178 children from 5 through 13 years of age and 40 adults answered questions about how they would remember times on different scales, how temporal memory is affected by retention interval, and the usefulness of different methods. The adults…

Studied the ages at which 240 children in grades one to five read and transformed times given in analog and digital displays, linked times to activities, and judged the order of hours in the day. Findings indicated that digital time reading was well developed by the first grade. (RJC)

Two experiments examined development of economic understanding among 5-, 7- and 9-year-olds. Found that most 5-year-olds understood the goal of acquiring desired goods, and most 7- and 9-year-olds also understood the goals of seeking profits, acquiring goods inexpensively, and competing successfully with other sellers. Results suggest that older…

Interviewed 5-, 6-, 7-, 8-, and 10-year olds, and adults regarding their knowledge about primary-consciousness, reflective-consciousness, and control activities. Found that the recognition that people do not engage in conscious mental activities when unconscious is still developing during the late middle-childhood years. (Author/KB)

When two-, three-, four-, and five-year-olds were tested for knowledge of sex role stereotypes and preferences for sex-typed activities, boys' stereotype acquisition lagged behind preference development. Girls' data were ambiguous. Boys displayed equally strong tendencies to endorse same-sex activities; girls displayed a stronger tendency to…

Argues that the operating characteristics of perceiving and remembering provide a foundation for progress on detailing the processes through which knowledge is realized in real-time tasks and in detailing the processes of developmental change. Includes three examples to illustrate how forming developmental hypotheses in terms of perceiving and…

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)