We present the results of an in-depth qualitative study that examined ninth graders' conceptual and procedural knowledge of fractions as well as their approach to mathematics learning, in particular fraction learning. We traced individual differences, even extreme, in the way that students combine the two kinds of knowledge. We also provide…

Sport is a context that provides positive developmental benefits to adolescents. However, these benefits are not distributed equally to all participants. This study examined whether the motivational constructs of attainment value and ability self-concept were related to positive developmental experiences in sport, and tested intensity of…

Peer aggression, victimization, and conflict are common occurrences during early adolescence. In the collection of articles in this special issue, several themes emerged, including the use of social psychological theory, individual difference variables, and social context. This article briefly reviews these articles and presents original data that…