Presented is an activity in which the pH of a solution can be quantitatively measured using a spectrophotometer. The theory, experimental details, sample preparation and selection, instrumentation, and results are discussed. (CW)

Discusses the need for laboratory demonstrations prior to experimentation. Describes an introductory computer-assisted manufacturing (CAM) course and includes suggestions for teachers. Provides a model exercise on train control. (YP)

Reviews three videotapes for physics teachers: (1) "Determination of the Newtonian Constant of Gravitation" showing the Cavendish experiment; (2) "Preview Film for RAM-Tutor Media" introducing a series of seven videocassettes covering physics; and (3) "Determination of the Velocity of Light" using a rotating mirror. (YP)

Meta analysis techniques were used to synthesize research on teaching students how to control variables when designing an experiment. The review included 65 controlled studies. Findings are reported in terms of the influence on effect sizes of characteristics of the study, instruments used, treatments applied, and results' utilities. (SLD)

Describes three activities: "Solar Approach to Ohm's Law," dealing with the Ohm's law and the inverse square law; "Using LED's to Demonstrate Induced Current," showing Faraday's law and Lenz's law by using light emitting diodes (LEDs); and "The Helium-Filled Organ Pipe," discussing a discrepancy between theory and experiment. (YP)

Explains strategies for motivating and getting student's attention in science. Presents a laboratory procedure for generating hydrogen using an Erlenmeyer flask and a one-holed stopper apparatus to fill a balloon which is used to produce a dramatic explosion. Safety precautions are cited. (RT)

Describes a lesson which integrates thinking, writing, and physics. Provides examples of student involvements, a list of typical topics, and additional notes to the teacher. (RT)

Presents an experiment to measure the threshold limit of the adhesion of water. Discusses types of thresholds and pseudo thresholds. Provides 13 examples of thresholds in science. (MVL)

This article discusses two data analysis methods: (1) Box plot; and (2) Outlier. Described are the procedures for drawing the two diagrams, wing median, quartiles, and highest and lowest values. (YP)

Discusses the use of linear regression methods to extrapolate experimental data. Describes the method of averages and two weighted least squares. Calculates the error range of each method. (YP)

Described are the techniques and results of using this tissue culture activity. Discusses the advantages of using such techniques in teaching alternation of generation life cycles to biology students. (CW)

Describes a demonstration to show the character and behavior of mixing clouds. Discusses laminar and turbulent flow, and the formation of contrails and other cloud phenomena. (CW)

Described are five physics activities including two superconductor projects, synchronizing video camera movements, electrical analysis of a bicycle, and apparatus for the measurement of thermal conductivity. (YP)

Discusses two strategies that provide concrete-thinking students with opportunities to develop and use formal or critical-thinking skills. Describes using task analysis and long-term investigations in the classroom. (YP)

Discusses the use of direct demonstration of the connections among the science process skills and the content areas of science. (MKR)