This study investigated income group differences in kindergartners' and first graders' (N = 161) arithmetic by examining the link between accuracy and strategy use on simple and complex addition problems. Low-income children were substantially less accurate than high-income children, in terms of both percentage of correctly solved problems and the…

Theoretical perspectives on spelling characterize development as a progression through qualitatively different phases or as a process of more or less continuous growth. This study investigated the potential utility of a different perspective, the overlapping-wave model, for characterizing spelling development (Rittle-Johnson & Siegler, 1999). In…

Groups of first-grade (mean age = 82 months), third-grade (mean age = 107 months), and fifth-grade (mean age = 131 months) children with a learning disability in mathematics (MD, n=58) and their normally achieving peers (n = 91) were administered tasks that assessed their knowledge of counting principles, working memory, and the strategies used to…