Two studies examine the convergence between measures of friendship and measures of liking in the assessment of friendship and peer acceptance. In the first study, 551 (301 boys and 250 girls) Canadian primary school children (ages 8-11) nominated friends and liked-most classmates. In the second study, 282 (127 boys and 155 girls) US primary school…

Socialization among aggressive friends is believed to play a critical role in the development of aggressive behavior. This study examined the moderating effect of norm salience in the classroom on the association between reciprocal friends' and children's own physical, relational, and general aggression. A total of 713 children (M = 10.32 years,…

Purpose: The objective of this study was to compare children with persistent versus transient preschool language delay on language, academic, and psychosocial outcomes in elementary school. Method: Children with persistent language delay (n = 30), transient language delay (n = 29), and no language delay (controls; n = 163) were identified from a…

This study examined the associations between intrinsic motivation and achievement in mathematics in a sample of 1,478 Canadian school-age children followed from Grades 1 to 4 (ages 7-10). Children self-reported their intrinsic motivation toward mathematics, whereas achievement was measured through direct assessment of mathematics abilities.…

This study assessed the genetic and environmental contributions to peer difficulties in the early school years. Twins' peer difficulties were assessed longitudinally in kindergarten (796 twins, "M"[subscript age] = 6.1 years), Grade 1 (948 twins, "M"[subscript age] = 7.1 years), and Grade 4 (868 twins, "M"[subscript…