Children start preschool with large individual differences in their early numerical abilities. Little is known about the importance of heterogeneous patterns that exist within these individual differences. A person-centered analytic approach might be helpful to unravel these patterns and the cognitive and environmental factors that are associated…

The authors investigated the performance on simple multiplication and division problems of 8-year-old children longitudinally to determine the developmental trajectories of both operations. Twice a year, during 2 consecutive school years, children performed a multiplication and division verification task and a number-matching task. All effects…

Examined the performance of kindergartners from middle- and low-income families on arithmetic calculations presented in a nonverbal format and in three verbal formats. Children from middle-income families performed better than those from low-income families on verbal calculation tasks but not on the nonverbal task. (BC)