In the present research, we provide empirical evidence for the process of symbolic integration of number associations, focusing on the development of simple addition (e.g., 5 + 3 = 8), subtraction (e.g., 5 - 3 = 2), and multiplication (e.g., 5 × 3 = 15). Canadian children were assessed twice, in Grade 2 and Grade 3 (N = 244; 55% girls). All…

Developmental delays in cognitive flexibility early in elementary school can potentially increase vulnerability for subsequent externalizing and internalizing psychopathology. The first goal of the current study was to identify latent subgroups of children characterized by different developmental trajectories of cognitive flexibility throughout…

The purpose of this study was to examine child-level pathways in development of prealgebraic knowledge versus word-problem solving, while evaluating the contribution of calculation accuracy and fluency as mediators of foundational skills/processes. Children (n = 962; mean 7.60 years) were assessed on general cognitive processes and early…

Recent studies reveal that children can solve proportional reasoning problems presented with continuous amounts that enable intuitive strategies by around 6 years of age but have difficulties with problems presented with discrete units that tend to elicit explicit count-and-match strategies until at least 10 years of age. The current study tests…

Teacher-child relationships have been linked to children's classroom engagement and to academic achievement. However, researchers have paid minimal attention to individual child factors that predict the development of these relationships. In the current study, we examined executive function (EF) prior to school entry as a predictor of…

This study examined the impact of a commonly adopted elementary universal social-emotional learning program, Second Step, on student social-emotional and academic outcomes following 2 years of implementation. The cluster-randomized wait-list control trial included 61 schools, 321 teachers, and 8,941 early elementary students across 2 states, with…

Research has established that long-term exposure to peer victimization is associated with higher levels of emotional and behavioral maladjustment. Yet, relatively little is known regarding predictors of stable versus declining victimization across extended periods of time. To fill this knowledge gap, the present study used latent growth curve…

Following a large, diverse sample of 4,096 children in 27 schools, this study evaluated the impact of 3 aspects of peer relations, measured concurrently, on subsequent child aggressive-disruptive behavior during early elementary school: peer dislike, reciprocated friends' aggressiveness, and classroom levels of aggressive-disruptive behavior.…

The link between behavior problems and low academic achievement is well established, but few studies have examined longitudinal relations between early externalizing behaviors before school entry and low academic achievement following transition to formal schooling. Early inattention has been particularly overlooked, despite strong associations…

Three complementary models of how peer relationship problems (exclusion and victimization) and aggressive behaviors relate to prospective levels of internalizing problems are examined. The additive risks model proposes that peer problems and aggression cumulatively increase risks for internalizing problems. The reciprocal risks model hypothesizes…

The study's goal was to identify the beginning of 1st grade quantitative competencies that predict mathematics achievement start point and growth through 5th grade. Measures of number, counting, and arithmetic competencies were administered in early 1st grade and used to predict mathematics achievement through 5th (n = 177), while controlling for…

The purpose of this study was to investigate the contributions of domain-general cognitive resources and different forms of arithmetic development to individual differences in pre-algebraic knowledge. Children (n = 279, mean age = 7.59 years) were assessed on 7 domain-general cognitive resources as well as arithmetic calculations and word problems…

Previous studies have found that children have difficulty solving proportional reasoning problems involving discrete units until 10 to 12 years of age, but can solve parallel problems involving continuous quantities by 6 years of age. The present studies examine where children go wrong in processing proportions that involve discrete quantities. A…