Discusses a laboratory exercise (suitable for the day before spring vacation) involving use of a hard-boiled egg to stimulate student responses to questions on the effect of adding salt to the water, formation of iron sulfide, ease of peeling, and gas laws. Additional experiments are included. (BC)

Describes an experiment on heat that utilizes only a styrofoam cup of coffee and a soda straw thermometer. (BT)

Presents demonstrations of chemical reactions by employing different features of various compounds that can be altered after a chemical change occurs. Experimental activities include para- and dia-magnetism in chemical reactions, aluminum reaction with base, reaction of acid with carbonates, use of electrochemical cells for demonstrating chemical…

Errors in determining the effectiveness of mouthwashes, disinfectants, and other household products as antibacterial agents may result from using broth cultures and/or irregularly shaped bits of filter paper. Presents procedures for a better technique and, for advanced students, two additional procedures for introducing quantitative analysis into…

Presented are procedures used to assay the activity of lipase during storage at three different temperatures. Since lipase solutions can decay even when refrigerated, it is recommended that the enzyme be freshly prepared prior to laboratory sessions in which they are used. (JN)

Describes a modified version of an experiment found in the laboratory manual "Chemistry" by Masterton, Slowinski, and Wolford (Holt, Rinehart and Winston, 1980). Accurate results (normally less than four percent error) in less time were achieved when magnesium turnings were used instead of magnesium ribbon called for in the original experiment.…

Describes modifications of a Nuffield experiment demonstrating oxygen transport by blood since the current experiment more often than not produces unsatisfactory results. Includes experimental modification, instructional strategy, assembly of equipment, and a brief discussion. (JN)

Presents nine physics notes for British secondary school teachers. Some of these notes are: (1) speed of sound in a steel rod; (2) physics extracts-part four (1978); and (3) a graphical approach to acceleration. (HM)

Describes a technique for the supercooling of water, for use in the science classroom, involving adding common salt to a mixture of ice and water. Several investigations are included for use during (and after) the process of supercooling. (DS)

Presents the following three biology notes: (1) a low cost variable temperature incubator; (2) projects on the ecology of freshwater mussels (Unionidae); and (3) studies on urease. (HM)

Presents 12 chemistry notes for British secondary school teachers. Some of these notes are: (1) a simple device for testing pH-meters; (2) portable fume cupboard safety screen; and (3) Mass spectroscopy-analysis of a mass peak. (HM)

Presents six middle school science notes for British science teachers. Some of these notes are: (1) fingerprints; (2) the floating magnet; and (3) the production of electricity using a lemon. (HM)

Describes a two-hour physics laboratory experiment modeling the phenomena of eclipsing binary stars developed by the Air Force Academy as part of a week-long laboratory-oriented experience for visiting high school students. (BT)

Describes the function of the various parts of the microscope and their integration in the formation of an optical image. Presents a procedure for setting up a microscope to obtain maximum resolution and contrast for each objective lens at all magnifications. (JRH)

A high school biology experiment is presented. The success of this experiment may be due to the inability to prove or disprove the hypothesis upon which it is based. (BB)