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

Discusses the rationale for using photochemistry to merge descriptive chemistry and molecular orbital theory in first-year chemistry courses. Includes procedures and safety information for various activities, demonstrations, and experiments involving photochemical reactions. (DH)

Describes a recently discovered and translated work by Archimedes in which he constructed a balance to determine the amount of gold in an alloy of gold and silver. A description of the balance (translated verbatim) as found in Archimedes' work "On Balances" is included. (JN)

Briefly discusses the theory of fatigue, and describes ways in which the fatigue rate in humans can be measured in the classroom using a simple physiological instrument, the ergometer. (JR)

Describes construction of two flashing light sources: an adjustable-rate battery-powered flasher and a neon tube powered by a 60-hertz electrical outlet. Both devices may be used for a variety of activities, including studies of free-falling object, pendulum period variation, and acceleration due to gravity. (JN)

Electrography is a technique in which unknown metals are identified by the precipitates they form with known electrolytes. The technique illustrates both electrochemistry and precipitation reactions. Describes the technique, suggesting its use in science and forensic science classes. (JN)

Describes activities (demonstrations/experiments) used to introduce history of periodic properties--without electrons, orbitals, filling shells, or any conception of atoms beyond Dalton's model. Activities supplement first chapter in a currently available chemistry text. Indicates potential danger of experiments if proper safety precautions are…

Four ways in which microcomputers can be turned into laboratory instruments are discussed. These include adding an analog/digital (A/D) converter on a printed circuit board, adding an external A/D converter using the computer's serial port, attaching transducers to the game paddle ports, or connecting an instrument to the computer. (JN)

Describes how plants can be produced by cloning by using tissue culture methods to mass-produce rare native prairie plants and trying to transfer some of the genetic characteristics of native grasses into cultivated cereals. The experiment was conducted at South Dakota State University. (HM)

Introduces an inquiry-based laboratory experiment in which students identify an unknown bacterial species by using techniques such as Gram staining. Uses an authentic problem solving approach in a scenario entitled, "What poisoned the apple juice?" (YDS)

Small-scale chemistry employs a modern design philosophy and small, inexpensive plastic apparatus to create a learning laboratory that fosters creativity, invention, and problem solving. This article describes the characteristics of the small-scale activities. A n-solutions chemical reaction matrix is provided with examples of classroom use. (YP)

Describes the Connecticut Academic Performance Test (CAPT) and explains the reasons for a curriculum change. Introduces CAPT-style labs which require students to identify a problem, ask questions, develop a hypothesis, design and conduct an experiment, analyze data, and draw conclusions. (YDS)