Children and adults often have difficulties comparing decimal magnitudes. Although individuals attempt to reconcile decimals with prior whole-number and fraction knowledge, conceptual and procedural differences between decimals and prior knowledge of whole numbers and fractions can lead to incorrect strategies. The dynamic strategy choice account…

The prevalence of tablet computer use among young children has risen dramatically, as have educational apps claiming to promote school readiness skills such as mathematical knowledge. Parents can contribute to their preschoolers' math readiness through the math talk they provide during everyday interactions in traditional nonelectronic activities.…

Little is known about whether and how parents can foster their children's spontaneous focus on number, an unprompted measure of attention to small numbers of objects that predicts later math achievement. In the current study, we asked 54 preschool-aged children and their parents to play together in a children's museum exhibit using either a…

Both mathematical language and the approximate number system (ANS) have been identified as strong predictors of early mathematics performance. Yet, these relations may be different depending on a child's developmental level. The purpose of this study was to evaluate the relations between these domains across different levels of ability.…

Are there differential benefits of training sequential number knowledge versus spatial skills for children's numerical and spatial performance? Three- to five-year-old children (N = 84) participated in 1 session of either sequential training (e.g., what comes before and after the number 5?) or non-numerical spatial training (i.e., decomposition of…

Children's sense of numbers before formal education is thought to rely on an approximate number system based on logarithmically compressed analog magnitudes that increases in resolution throughout childhood. School-age children performing a numerical estimation task have been shown to increasingly rely on a formally appropriate, linear…

Prior studies indicate that children vary widely in their mathematical knowledge by the time they enter preschool and that this variation predicts levels of achievement in elementary school. In a longitudinal study of a diverse sample of 44 preschool children, we examined the extent to which their understanding of the cardinal meanings of the…

Focused on cardinality acquisition (thought to be crucial to correct counting) and on the relation between cardinality and counting. Gathered data with three groups of children three to five years old on four kinds of tasks. Found no empirical evidence for considering counting as a single prerequisite to cardinality. Suggests new approach to…

Investigated the development of number concepts and addition skills in Japanese children. Found that children's use of addition strategies, rather than their solution accuracy, changed primarily as a function of schooling, not age. Children's Base 10 number concepts improved with the amount of schooling, as well as with other social and…