Reported are the effects of a conceptually oriented unit on decimal fractions. The relationships between short-term changes in solving processes and the stability of these processes over time, performance of students, and entry achievement level and the long-term effects of conceptually based instruction are discussed. (KR)

Investigated is whether children would spontaneously model problems with superfluous information and whether their modeling would facilitate problem solving. Included are the addition/subtraction story problems used in this study, introduction, method, results, discussion, and conclusions. (KR)