Children's ability to discriminate nonsymbolic number (e.g., the number of items in a set) is a commonly studied predictor of later math skills. Number discrimination improves throughout development, but what drives this improvement is unclear. Competing theories suggest that it may be due to a sharpening numerical representation or an improved…

Children's ability to discriminate nonsymbolic number (e.g. the number of items in a set) is a commonly studied predictor of later math skills. Number discrimination improves throughout development, but what drives this improvement is unclear. Competing theories suggest it may be due to a sharpening numerical representation or an improved ability…

The present study tests two predictions stemming from the hypothesis that a source of difficulty with rational numbers is interference from whole number magnitude knowledge. First, inhibitory control should be an independent predictor of fraction understanding, even after controlling for working memory. Second, if the source of interference is…

Drawing on Geary's (1995) evolution-based model of cognitive and academic development, this study investigated the relation between biologically primary skills (vocabulary, executive functions, and visual-spatial processing) and subsequent word reading and calculation. It also examined the extent to which these relations were mediated by…

A growing literature reports significant associations between children's executive functioning skills and their mathematics achievement. The purpose of this study was to examine if specific early number skills, such as quantity discrimination, number line estimation, number sets identification, fast counting, and number word comprehension, mediate…

Early number sense knowledge is highly predictive of later math achievement (Herbers et al., in press; Jordan, Kaplan, Ramineni, & Locuniak, 2009; Obradovic i et al., 2009). However, research suggests that variables beyond number competencies contribute to students' mathematics achievement, most notably, executive function (Blair & Razza,…

The present study tested the "interference hypothesis"-that learning and using more advanced representations and strategies requires the inhibition of prior, less advanced ones. Specifically, it examined the relation between inhibitory control and number line estimation performance. Experiment 1 compared the accuracy of adults' (N = 53)…