Describes the benefits and techniques of having students create models of chemical compounds. This hands-on approach uses colored paper and other inexpensive materials to construct the models. A step-by-step approach provides objectives, materials, an explanation on how to calculate chemical ratios, procedures, follow-up activities, and a resource…

The pencil-and-paper assignment "Represent water in its three states using a model" was given to pupils (n=227) from eighth to twelfth grades. The findings show that the dominant model used was the space filling type; movement of particles was indicated by a minority of pupils; size of the model changed when drawn in different states.…

Describes a science project in which students make models of polymers using polyvinyl alcohol solution. Students make T-shirts using polymer paint to remind them of their activities. (MDH)

Describes a conceptual typology of models to help teachers select models appropriate to the cognitive ability of their students. Presents an example of how the systematic presentation of analogical models enhanced an 11th-grade chemistry student's understanding of atoms and molecules. Makes recommendations for teachers. Contains 28 references.…

The purpose of this review is to provide a model for studying genetic association of response to intervention in child language disorders. In addition to a theoretical overview and review of different approaches to studying candidate genes, a specific methodology for completing this type of analysis is presented. The goal of the analysis is to…

Chemistry is commonly portrayed at three different levels of representation--macroscopic, submicroscopic and symbolic--that combine to enrich the explanations of chemical concepts. In this article, we examine the use of submicroscopic and symbolic representations in chemical explanations and ascertain how they provide meaning. Of specific interest…

We report on an educational project in particle physics based on Feynman diagrams. By dropping the mathematical aspect of the method and keeping just the iconic one, it is possible to convey many different concepts from the world of elementary particles, such as antimatter, conservation laws, particle creation and destruction, real and virtual…

The purpose of this study was twofold: (1) to understand the conceptual frameworks that sixth-grade students use to explain the nature and structure of matter and molecules; and (2) to assess the effectiveness of two alternate instructional units in helping students change those conceptions. The study involved 15 sixth-grade classes taught by 12…

Describes two secondary-level classroom games designed to teach the balancing of chemical equations and the principles of chemical bonding. (MLH)

Differentiates between chemical nomenclature and the common ways that substances are named and described. Students should learn the chemical nomenclature so that they will be more observant and objective. Cites examples of student misconceptions based upon their own imagination and logic. (TW)

Discusses the production and use of polymer materials as thermal insulators. Lists several materials that provide varying degrees of insulation. Describes the production of polymer foam and focuses on the major applications of polystyrene foam, polyurethane foam, and polyisocyanurate foam. (TW)

Discusses electron-loss spectroscopy and the experimentally observed excitation energies in terms of qualitative MO theory. Reviews information on photoelectron spectroscopy and electron transmission spectroscopy and their relation to the occupied and unoccupied orbital levels. Focuses on teaching applications. (ML)

Outlines a multistep project involving oxidation of cholesterol, isomerization of an enone, and reduction of delta-4-cholesten-3-one. Featured is the last stage in which the ring junction is set stereospecifically. Recommends two laboratory periods to complete the reaction. (ML)

Describes two introductory exercises designed to teach the fundamental ideas and methods of crystallography, and to convey some important features of inorganic and organic crystal structures to students in an advanced laboratory course. Exercises include "The Crystal Structure of NiO" and "The Crystal Structure of Beta-Fumaric Acid." (CW)

Discusses advantages of nematode use for studying patterns of cell division, differentiation, and morphogenesis. Describes nematode development. Cites experimental approaches available for genetic studies. Reviews the topics of control of cell division and differentiation, the nervous system, and muscle assembly and function of the organism. (RT)