Increasingly, science teachers are seeking phenomena that will allow them to explore both scientific content and socially relevant issues. The authors describe a series of lessons that (1) model the exoneration of wrongly convicted individuals using the science of DNA analysis and (2) contextualize individual cases within a larger system where…

Animal dissection is practiced to varying degrees around the world and is particularly prevalent in North America throughout all levels of education. However, a growing number of studies suggest that nonanimal teaching methods (NAMs) (e.g., virtual anatomy tools and three-dimensional models) are better for achieving learning goals compared to…

Defends cookbooks and lab manuals. Both can provide reliable procedures; are good places to start; and need not stand in the way of understanding, insight, or imagination. (MM)

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…

Includes methods for using harmonographs in demonstrating motion of pendulums, constructing an electrostatic "bell," inverting mirror images, demonstrating the corrosion rate of steel, demonstrating expansion, studying rate of reaction between magnesium and hydrochloric acid, using matchboxes in science for containers, problem boxes, building…

The effects of temperature and pressure on the collapsing of soda cans are discussed. The use of various temperatures and substances for the cooling bath are described. (KR)

A procedure that allows students to view an entire bacterial growth curve during a two- to three-hour student laboratory period is described. Observations of the lag phase, logarithmic phase, maximum stationary phase, and phase of decline are possible. A nonpathogenic, marine bacterium is used in the investigation. (KR)

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…

Describes a method of staining that makes details clear and dispenses with the time-consuming use of chemicals. The Rheinberg differential color illumination, (or optical staining) is strikingly beautiful and is especially useful with living or nonliving unstained, transparent specimens. Color photographs of sample specimens are included.…

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…

A mechanical analogy between the microscopic motion of a charged carrier in an ordinary resistor and the macroscopic motion of a ball falling along a slanted board covered with a lattice of nails is introduced. The Drude model is also introduced to include the case of inelastic collisions. Computer simulation of the motion is described. (KR)

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)

A discussion is presented on the role of secondary teachers in public schools, followed by a sequence for teaching oxidation-reduction in secondary school chemistry courses. (BB)