Third, fifth, and seventh graders selected the best strategy (rounding up or rounding down) for estimating answers to two-digit addition problems. Executive function measures were collected for each individual. Data showed that (a) children's skill at both strategy selection and execution improved with age and (b) increased efficiency in executive…

Children's understanding of the inversion concept in multiplication and division problems (i.e., that on problems of the form "d multiplied by e/e" no calculations are required) was investigated. Children in Grades 6, 7, and 8 completed an inversion problem-solving task, an assessment of procedures task, and a factual knowledge task of simple…

Earlier research [Discourse Process. 23 (2/3) (2002) 135] on argumentation suggests that adults use advanced discourse strategies more consistently, more frequently, and more flexibly than do adolescents. The present study examines the development of argumentation skills during adolescence. Forty-eight seventh and eighth graders were assigned to…