Describes a demonstration to illustrate the importance of knowing what is supposed to be learned before studying begins. Suggests that the exercise may be used to show the basic elements of a scientific experiment. Explains that attention's effect upon memory is shown by students' tendency to remember best what they are told to remember. (DK)

Presents an experiment to demonstrate Charles's Law of Ideal Gases by creating a constant-pressure thermometer from materials that can be found in the kitchen. Discusses the underlying mathematical relationships and a step-by-step description of the experiment. (MDH)

An activity that uses dandelions to show the phenomenon of geotropism is described. The process of sedimentation, which causes the bending, is observed at moderate magnification under a standard microscope. A list of needed materials, directions for the tissue dissection, and time-lapse photographs of the process are included. (KR)

Discusses the essential electrical characteristics of a particular model of soldering gun. Presents four classroom demonstrations that utilize the soldering gun to test the following geometrics of wire loops as electromagnets: (1) the original tip; (2) a single circular loop; (3) a Helmholtz coil; and (4) the solenoid. (MDH)

Presents activities that utilize balloons to encourage students to explore questions related to scientific concepts. Concepts explored include light, heat, charged ions, polarization, and the sense of smell. (MDH)

Approaches used to evaluate student progress depend on the educational philosophy involved, because each philosophy determines what learners should learn. Approaches reviewed include (1) the testing movement; (2) self-evaluation by students; (3) idealism and the evaluation process; (4) experimentation and evaluation; and (5) perennialism and…

Described is a LOGO computer program that enables students to investigate the relationship between a digital number and the resistance in a variable resistor used to generate that number. Likewise, actual temperature readings and the corresponding resistance within a thermistor can be used for data gathering and subsequent analysis. (JJK)

Seven qualitative issues associated with randomization that have the potential to weaken or destroy otherwise sound experimental designs are reviewed and illustrated via actual field experiments. Issue areas include ethics and legality, liability risks, manipulation of randomized outcomes, hidden bias, design intrusiveness, case flow, and…

A simple experimental arrangement that makes it possible to simultaneously observe and compare on a screen the two interference patterns produced by reflected and transmitted light from incident white light impinging on a soap film directly is described. Procedures and illustrated effects are discussed. (CW)

Two experiments which can be used to illustrate light diffraction using compact disks are detailed. Included are procedures, computations, and probable results. (CW)

Describes the use of practice weighings and handling of fluorescent compounds to assist in teaching students safe-handling techniques. (PR)

Describes the prosecution efforts regarding a chemistry teacher when one of the teacher's students was injured in an explosion in an attempt to make gun powder. In a different section, discusses nonscientists in science laboratories and the responsibilities of competent persons. (PR)

Describes an experiment to induce carbon dioxide deficiency to demonstrate its effects on plant growth. Suggests further studies to examine respiration by soil microbes and the effects of relative humidity, other gases, and air pollution on plant growth. (MDH)

Describes experiments with chewing gum for students to learn about the scientific method. Students classify various types of gum and then do a self-designed consumer product test. (PR)

Describes science experiments for undergraduate biology instruction on the concepts of mutation and characterization of the resulting mutant strains. The filamentous fungi "Fusarium moniliforme" is used to illustrate the induction of mutants (mutagenesis), identification of the mutated gene, construction of a biochemical pathway, and…