A diffusion cell to model the permeation of salicylate drugs through the skin using low-cost materials and a sensitive colorimetric analytical technique is described. The diffusion apparatus has been used at a further education college by a student for her AS-level Extended Project to investigate the permeation rates of salicylic acid…

Lists directions for creating some laboratory equipment that makes it easier for students to assess the rate at which an enzyme is modifying its target (substrate). (WRM)

Begins with the procedure and results from an investigation on the effect of fluoride on the reaction between eggshell (substitute teeth) and dilute ethanoic acid. Describes an elegantly modified and improvised apparatus. (DDR)

Summarizes the benefits of using hydroponics in school for investigational work. Lists requirements and includes advice on suitable plant choices. Outlines the various growing systems and growing media and provides suggestions for science investigations using hydroponics. (DDR)

Describes the construction of a model suitable for demonstrating the principles of refrigeration in secondary science classes. (JR)

Presents seven selected biology notes which could be used in the school biology courses. Each includes the name of the author and a description of activities suggested. (HM)

Described are filming of laboratory activities in 14 classes to determine class movement time, pupil centered activity time, and teacher centered activity time. Proportions of times ranged as follows: movement, 4-21 percent; pupil centered, 29-85 percent; teacher centered, 11-64 percent. (SL)

Discusses several alternatives to the use of laboratory animals in investigating biomedical problems. Alternatives include tissue culture, use of plant and bacterial material, redesigning experiments, and construction of mathematical and computer models. (CS)

Includes procedures for demonstrating anaerobic respiration in peas, isolating virgin Drosophila females, solving mortality problems in young gerbils, measuring dissolved oxygen, constructing models for transpiration and DNA molecules, freezing chick embryos, mixing nutrient media, illustrating Darwinian ecological principles, and detecting…

Includes methods for determining melting and boiling points, illustrating the Finkelstein reaction, choosing acid-base indicators, growing perfect NaC1 cubes and "whiskers," bromination of alkenes, using vanadium in the laboratory, preparing phenylamine-copper (II) sulfate (VI) complex, simulating first-order chemical kinetics on a programmable…

Includes methods for demonstrating Schlieren effect, measuring refractive index, measuring acceleration, presenting concepts of optics, automatically recording weather, constructing apparaturs for sound experiments, using thermistor thermometers, using the 741 operational amplifier in analog computing, measuring inductance, electronically ringing…