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…

Direction dependence analysis (DDA) is a recently developed method that addresses the need for more sophisticated tools to evaluate causal mechanisms of developmental processes and interventions. The present study applied DDA to evaluate the hypothesized mediators of a classroom behavior management training program on student academic competence.…

What is the role of oral language in reading competence during the transition to school? Is oral language in preschool best conceptualized as vocabulary knowledge or as more comprehensive language including grammar, vocabulary, and semantics? These questions were examined longitudinally using 1,137 children from the National Institute of Child…

Adopts a longitudinal design to track mother-child developmental change in infant task-related mastery and concomitant maternal behavior. Finds that, as infants gain more mastery across time, mothers gradually withdraw support in terms of concrete, specific and nonverbal means of instruction. Results support a one-step-ahead model for maternal…