Presents an examination of the buoyancy principle which can serve as a simple but rigorous illustration of a falsification test that not only clears up a possible misconception but also points the way to a number of practical uses of buoyancy measurements that have not generally been recognized. (MVL)

Discussed are selected application and future trends in supercritical fluid chromatography (SFC). The greatest application for SFC involves those analytes that are difficult to separate using GC or LC methods. Optimum conditions for SFC are examined. Provided are several example chromatograms. (MVL)

Discussed is a method of measuring the coefficient of linear expansion of a solid. Getting many data points, using a computer program using the least square fit technique, and modifying the apparatus are described. (YP)

Described are three physics experiments: (1) "Holographic Prism"; (2) "Teaching about Energy with the Gravicar"; and (3) "The Coherer." In each experiment, a brief description of the experiment devised is provided with diagrams and references. (YP)

Discusses the mechanism and the change of pH during the reaction. Notes that a dramatic rise in pH occurs when the reaction nears completion. Evaluates theories by other authors. (MVL)

Gives upper level chemistry students a better understanding of the application of lasers in the field of spectroscopy. Provides three experiments to demonstrate the thermal lens effect: determination of beam profile, cell position optimization, and pKa determination. (MVL)

Explains the development of a science program which was initiated to help students, parents, and other teachers appreciate science. Provides a list of materials needed, procedures, questions, and objectives for performing two of the 30 activities used in the project. (RT)

This article presents a variety of topics discussed in this column and at a biology teachers' workshop concerning the quality and value of lab techniques used for teaching high school biology. Topics included are Drosophila salivary glands, sea urchins, innovations, dyes and networking. (CW)

Provided are background information, equipment lists, and procedures for four activities for teaching aquatic ecology. Activities include "The Aquatic Food Chain Game"; "Two-Liter Aqua-Vivariums"; "A Sealed World"; and "Weaving a Web: Evaluation." (CW)

Contains articles on digestive enzymes in grasshoppers; bird and badger observation; reactions between hydrochloric acid and sodium carbonate solutions; observing the migration of ions; pupil's heating skills (Bunsen burners); photolysis experimentation; capillary kinetics; experience with trireme; connection circuits; special relativity; a…

A computer-based replacement for an electronics laboratory experiment was created and tested on second-year undergraduate students in the Department of Mechanical Engineering at the University of Southampton (England). Responses, assessed by questionnaire, showed that computer-assisted learning techniques provide a viable means for teaching…

Three articles focus on many classroom activities and experiments inspired by the voyage of two canoes, built of traditional materials, from Hawaii's Hilo Harbor in 1995. Nationwide, students followed daily satellite tracking, accessed the Internet for updated accounts of the canoes, talked directly with navigators, and watched television…

Describes the implementation and evaluation of a nondirected student research project that aimed at acquainting students with some of the procedures used by physicists in the real world. Outlines specific project designs used by the students. (JRH)

This commentary on EC 608 301 points out that devotion to the natural science canon of experimental proof in the area of generality testing requires proof procedures that are difficult, expensive, or impossible, but adopting a different canon of proof will not produce the desired certainty about the accuracy of the answer. (JDD)

Presents an alternative to the use of a radar to determine how fast an individual can serve a tennis ball. Equipped with a tape recorder and a Macintosh computer, students determine the velocity of a tennis ball by analyzing the sounds and echoes heard on the court. (ZWH)