Understanding fraction magnitudes is foundational for later math achievement. To represent a fraction x/y, children are often taught to use "partitioning": Break the whole into y parts and shade in x parts. Past research has shown that partitioning on number lines supports children's fraction magnitude knowledge more than partitioning on…

Recently, there has been increasing evidence showing that males estimate whole numbers more accurately than females on the number line. However, relatively little is known about what factors contribute to this gender gap. The current study explored potential mediators of the gender difference in number line estimation, including spatial skills and…

Children practice their spatial skills when playing with spatial toys, such as construction materials, board games, and puzzles. Sex and SES differences are observed in the engagement in such spatial play activities at home, which relate to individual differences in spatial performance. The current study investigated the effects of explicitly…

Ratings of concreteness and picturability and production data for meaningfulness of 310 words were gathered from sixth-grade children and college students. (JMB)

Changes in the performance levels of 41 elementary school-aged girls on Euclidean geometric operations tasks were related to changes in forms of their drawings of two anticipated rotation movements. Operatory and imagery performance were measured in three sessions over a 3-year period. (JMB)

Reports four experiments with preschool and elementary school children. The first study involved a localization task and the remaining three required the mental manipulation of spatial information. (Author/SDH)