Explains the concept of stretch reflexes to students using a mechanical model. The model provides a dynamic multisensory experience using movement, light, and sound. Describes the construction design. (SAH)

A laboratory activity that can be used at a number of levels from high school to college is discussed. This activity can be used to teach chemical concepts such as oxidation and reduction, stoichiometry, acids and bases, pH, nucleophilic reactions, conjugation, leaving groups, complexation, solubility, and reversibility.

Describes a classroom demonstration supported by the guided-inquiry experience that focuses on separation techniques and other solvent-dependent processes, such as reaction-solvent selection. (Contains 13 references.) (YDS)

Uses Galileo's 'jumping-hill' experiment as an historical element to improve science teaching in the classroom. Illustrates that the experiment can stimulate an animated discussion in the classroom, even if precise historic circumstances are not mentioned. The historical dimensions bring some color into the lesson, which increases attention. (SAH)

An exercise that uses a common bacterium, E. coli, in great numbers, to detect a demonstrable change in the ability of some cells to become resistant to the common antibiotic streptomycin is presented. The procedure for preparing and pouring the gradient antibiotic plates is provided. The advantages of using the Basic Fuchsin in the agar are…

Evaluates the traditional method of intercalating theoretical and seminar classes with laboratory practical work. Proposes a new schedule where students get problem-based learning of theoretical concepts during the first half of the course, and plan and execute a laboratory project during the second half. (Author/CCM)

Saccharomyces cerevisiae provides an excellent tool for students to enter into inquiry-based science. This very simple organism is used to demonstrate that the principles governing life apply to all organisms. Students learn to design experiments using trypan blue and heat, build upon their findings with new experiments, and refine and repeat…

Traces the inception of laboratory activities in the instruction of physics in American secondary and higher education institutions. In particular, the impact of Edwin Hall on secondary school physics instruction is described. (CP)

The consolidation of the theoretical concepts as well as the use and learning of experimental techniques that are compatible with the technological evolution has been the main goals in Thermodynamics and Heat Transfer and Thermal Systems Laboratories at Escola Politecnica of University of Sao Paulo. The infra-structure and experimental benches in…

A list of demonstrations of discrepant events which have been found to stimulate the curiosity of students in science at the secondary school level are presented. A brief description of the materials and procedures for 15 of these demonstrations is outlined, with short explanations of concepts and principles involved. (MP)

Describes a laboratory exercise to demonstrate enzyme activity using gelatin and meat tenderizer. The exercise is adaptable to any grade level. (MA)

Explores a way of analyzing laboratory activities that can help middle and high school science teachers to match their instructional goals with one of three appropriate types of activities: confirmation, generalization, or resolution. Examples and guiding principles for each kind of activity are given. (Contains 23 references.) (MDH)

A procedure for purifying DNA using either bacteria or rat liver is presented. Directions for doing a qualitative DNA assay using diphenylamine and a quantitative DNA assay using spectroscopy are included. (KR)

Describes a series of science activities involving dissection and analysis of a sea necklace. (CP)

In this section, brief contributed articles on a variety of secondary school science topics appear. (CP)