Presents a device to illustrate the concepts of entropy of mixing and the contribution of one term in the Gibb's equation. Notes the device is relatively easy to construct and provides a visual demonstration on diffusion. (MVL)

Examines two computer interfaced lab experiments: 1) discusses the automation of a Perkin Elmer 337 infrared spectrophotometer noting the mechanical and electronic changes needed; 2) uses the Gouy method and Lotus Measure software to automate magnetic susceptibility determinations. Methodology is described. (MVL)

Presents techniques used for disinfestation of plant material, preparation of equipment and media, and laboratory procedures for tissue culture using cauliflower. Details methods for preparing solutions and plant propagation by cloning. (CW)

Considers three common cases of localized corrosion of metals: pitting, crevice, and stress corrosion. Provides experimental methods for studying all three methods. Includes a discussion of expected results. (ML)

Describes an experimental procedure for determining trihalomethanes (THMs) in liquids by gas chromatography. Provides recommendations for reactants and supplies to obtain acceptable results. Discusses the analysis of water from various sources: pools, lakes, and drinking water; compares these to three cola drinks. (ML)

The harmful effects of smoking tobacco are discussed. Instructions, lists of materials, and discussion questions for three activities to investigate these effects are provided. A glossary of tobacco-use terms is given. (CW)

Tests in each science area were developed around six laboratory tasks. Students had to plan an investigation, collect and organize data, and formulate conclusions based on calculations and graphs. Over 1,000 students from 32 Ohio schools formed the sample for this study. Data are presented by skill and by task. An analysis for gender and school…

With thousands of activities available, how does a teacher select activities appropriate for the classroom? Describes the guidelines of the "Science Activity Filter," which provide a useful protocol for evaluating science activities for their value in the classroom, allowing the teacher to use resources effectively, minimize discipline and safety…

Outlines 39 physics demonstrations that utilize simple objects such as coffee and soda cans to illustrate scientific concepts. (12 references) (MDH)

Proposes the V-Scope as a teaching aid to measure, analyze, and display three-dimensional multibody motion. Describes experiment setup considerations, how measurements are calculated, graphic representation capabilities, and modes of operation of this microcomputer-based system. (MDH)

Proposes methods by which laboratory practical exams may be structured to assess outcomes from laboratory instruction. Presents eight general considerations for writing and using practical exams. Describes four example laboratory exams involving a box camera, circuit boxes, floating objects, and light. (MDH)

Presents a class activity in which students use trigonometry to calculate the height attained by a water rocket. Provides a lesson plan that includes a list of materials needed, procedures to carry out the experiment, suggestions to extend the activity, and a reproducible worksheet for the students to register their calculations. (MDH)

Uses computers to help students identify variables controlling pendulum period. A program written in BASIC for the Apple computer is provided. The activities are useful for developing science skills, mathematics skills, and computer skills. (PR)

Provides background information on DNA fingerprinting, and describes exercises for introducing general biology students at the high school or college level to the methodology and applications of DNA fingerprinting. (PR)

Describes how lectures, laboratories, and role playing can be used to introduce students to the importance of water quality of water used for plant growth. (PR)