Describes a design for a hand-held conductivity tester powered by a 9V battery that gives semi-quantitative results for aqueous electrolyte solutions of concentrations ranging from 0.001 M to 0.1 M. The tester uses a bar-graph LED driven by an LM3914 integrated circuit to indicate the level of conductivity. A list of parts, procedures, and results…

Most children become excited about science because they can do something and because they can watch the results. These are some of the answers most elementary school students tell you when they are asked about science class. It has been substantiated by decades of research that experiential experiences are exciting and remembered, visual and…

Describes modifications and procedures needed for parasitic lampreys to be kept in a closed system. Presents information dealing with obtaining the organisms, tank modifications, temperature, feeding, disease prevention, and animal welfare. A discussion is included. (RT)

Discussed is the integration of microcomputers into the science laboratory curriculum. The approach provides an exposure to important aspects of computer technology while preserving concrete experiences provided by hands-on laboratories. (CW)

Describes a spectrophotometric titration experiment which uses a manual titration spectrophotometer and manually operated buret, rather than special instrumentation. Identifies the equipment, materials, and procedures needed for the completion of the experiment. Recommends the use of this experiment in introductory quantitative analysis…