An experiment for determining polychlorinated biphenyl (PCB) isomers is described. The very low vapor pressures of PCB's allow them to be handled safely in the laboratory. In addition, this low volatility permits their analysis by thin-layer chromatography and recovery from the developed plate with effectively no evaporative losses. (JN)

Provides additional recommendations as the Health and Safety at Work Act of 1974 applies to the storage of flammable liquids, provision of safety equipment, responsibility for technicians and faulty apparatus. (GS)

Correlation, the connection between lecture class content and related laboratory experiences, is a vital ingredient for the successful occupational class but it must be planned. (KP)

Describes methods that can be used by beginning chemistry and geology students for growing, cutting, and polishing alum crystals. (JR)

Describes methods and procedures for killing, preserving, mounting, and displaying insects. (JR)

Three programs of individualized instruction in a mathematics laboratory for the community college student are described. Problems and advantages of the programs, including costs; student dropout rate; teacher role; design, operation and management of the laboratory, and grading are discussed. (DT)

It is shown that students have no difficulty scaling small diameter standard wall tubing if an explanatory sequence is incorporated into the experimental writeup. (DF)

Two games, a barn dance and football game, are described in which the rules and the strategies are based on the composition of elements of the Klein-four group. (DT)

Describes the equipment and procedures used to demonstrate (1) light interference with teacher-made photographic film gratings, (2) the minimum angle of deviation for the various lines of a spectrum, and (3) electrostatic phenomena. Written for the high school physics teacher. (LC)