Covers a project conducted by the Freudenthal Institute in which observation of student behavior supported the premise that the graphics calculator can stimulate the use of realistic contexts, the exploratory approach to mathematics, a more integrated view of mathematics, and more flexible behavior in problem solving. (AIM)

Mental arithmetic strategies were studied with 91 Dutch third graders who computed by splitting off 10s and units in both numbers or counting by 10s up or down from the first unsplit number. Results reveal flexibility in changing between and within strategy use. Implications for instruction are discussed. (SLD)

Demonstrates how mathematics is a changing science through an in-depth look at the history of the development of logarithms. Serves as a reminder to continue to remember and appreciate the efforts and contributions of past mathematicians. (KHR)

Presents an issue that arises in every country: How can teachers best help children master basic addition and subtraction facts? Discusses how this is handled in China and highlights the impact that language has on how children think about numbers. (KHR)

Describes how open-ended writing prompts provide a window into student understanding and mathematical thinking. (YDS)

Described is an activity in which students examine data collected from an official report of a train accident to evaluate the conclusions of the official investigation. Quotations from the records and calculations used in this activity are included. (CW)

Presented are problems that teachers can use to stimulate students' thinking about the subject of mathematical scaling. Food and eating examples are used to illustrate this concept. (CW)

Provided is a rebuttal to an argument concerning the use of Ka values for water and the hydronium ion. The derivation of new values as a result of the treatment of the water as the solvent and using a Raoult's Law standard state is discussed. (CW)

Presented is a script for a classroom presentation introducing weighted means and geometric means to students who are already familiar with arithmetic means. Frequent questioning is included to keep the students mentally active and involved in the development of this new idea. Typical student responses to these questions are provided. (CW)

Presented are two examples of real-life examples that can be used to promote or exemplify concepts of probability and statistics. Details of the calculation of these probabilities are given. (CW)

The design and data management of an activity to study weathering by increasing the rate of mineral dissolution in a microwave oven is described. Data analysis in terms of parabolic and first-order kinetics is discussed. (CW)

This article develops an algorithm to find all solutions to the problem, making all sums of a hexagram's nine lines the same. It shows how to exploit the geometric structure of the hexagram and its group of automorphisms. (YP)

Discussed is some of the confusion encountered in electrochemistry due to misunderstandings of sign conventions and simple mathematical errors. Clarified are issues involving emf series, IUPAC sign conventions, calculation of cell potentials, reference electrodes, the polarity of electrodes in electrochemical devices, and overpotential. (CW)

Experiments in strategy instruction for mathematics have been conducted using three models (direct instruction, self-instruction, and guided learning) applied to the tasks of computation and word problem solving. Results have implications for effective strategy instruction for learning disabled students. It is recommended that strategy instruction…

Examined factors that influence children's competence in mathematics when they begin first grade. Results indicated that parent education, family economic resources, and parent expectations influenced children's competence. Race and family structure, when considered apart from other variables, were not significant influences. (PCB)