Unusual experiments in sound are described. Sounds produced from the vibration of areas are represented by many beautiful sand patterns. The vibrating areas vary from square to circular plates. (SA)

Tips are given for collecting and identifying diatoms for use in secondary school biology classes. Collecting sites described vary from freshwater to terrestrial habitats. (SA)

Explains how to use sticky tape, a soda straw, and a little water to build a device which will demonstrate Charles' law as well as give the temperature. (GA)

Provides step-by-step instructions for constructing a simple, inexpensive microscope. Illustrated with photographs and a drawing. (MA)

Describes instruments for the quantitative measurement of radioactively tagged organic and biological molecules used as tracers. (MLH)

Investigates the five most common reasons teachers give for not involving students in hands-on classroom activities: too much work, too chaotic, lack of teacher science content knowledge, incompatibility with the curriculum, and lack of materials. Provides strategies for avoiding these excuses. (DDR)

Describes variations on atmospheric pressure demonstrations and some systematic studies. Demonstrations use steam, generated either externally or internally to the container, to sweep out residual air. Preferred vessels collapsed slowly. Demonstrations use plastic milk jugs set in layers of aluminum foil, pop bottles immersed in 4-L beakers…

Discusses advantages of the Stirling engine. Describes the details of constructing one from common materials, and its use for studying thermodynamics. (YP)

Introduced are two experiments: radon detection method shows real data using vacuum cleaner, soft toilet paper, and Geiger-Muller tube; critical potentials measurement describes the operation of Teltron tube with VELA. (YP)

Explains mechanisms of 19th-century vacuum pumps. Describes demonstrations using the pump including guinea and feather tube, aurora tube, electric egg, Gassiots cascade, air mill, bell in vacuum, density and buoyancy of air, fountain in vacuum, mercury shower, palm and bladder glasses, Bacchus demonstration, pneumatic man-lifter, and Magdeburg…

Described is a position transducer used to convert the position of an object into a voltage read by a computer with use of an interface board. The arrangement of the apparatus, electronic circuit, and typical graph displays are presented. Discussed is the instructional use of the transducer. (YP)

Describes the physics displays at the University of Canterbury (New Zealand), including the facility, static displays, and interactive displays. Discusses the basic philosophy, general principles, and evaluation of the displays. (YP)

Discusses a heavy-duty KBr press that will allow undergraduate students to prepare KBr windows in room-temperature conditions. Described are the essential components and the procedures for the KBr window preparation. (YP)

Discusses a tutorial slide package for oscilloscope operation. Provides source address and price for obtaining it. (YP)

Describes the Packard's Falling Body Apparatus, invented by John C. Packard, which is essentially an inclined plane combined with a simple and elegant method of measuring the relative time of descent of a steel ball. (JRH)