Discusses overall mental computation achievement and limits discussion to strategies middle school students used when computing with whole numbers, decimals, and fractions. Suggests that the development of conceptual knowledge of numbers is an important prerequisite for the understanding of mental computation procedures. (Contains 31 references.)…

Provides an overview of the conceptual analysis of the unit fraction that provided the framework for developing a comprehensive array of fraction activities for fourth-grade students. Reveals the students' difficulties in learning the unit-fraction concept and discusses the didactical implications of these difficulties. Contains 15 references.…

Describes a teaching experiment conducted over a period of four consecutive days with 13 fourth grade students who had already completed a unit of fractions to determine whether problematic size was the ordering criteria. Concludes that children can indeed order fractions as they do natural numbers. (Contains 11 references.) (ASK)

Elementary and middle school education majors in Australia (n=326) and the United States (n=378) were asked to arrange a list of decimals in order from smallest to largest. Only about half of these preservice teachers in each country were able to complete the task correctly. (MKR)

Illustrated first is the case in which a wrong procedure (with fractions) leads to a correct result. Trying to justify why it works in this case and looking for similar patterns involved interesting algebraic considerations as well as use of computers. (MNS)

Children in grades four and five had instruction on fractions with a continuous manipulative aid to help transfer their knowledge to tasks with a discrete manipulative aid. Results suggest that discrete-embodiment tasks are more difficult than continuous-embodiment tasks. (MNS)