Presents a lab to analyze plant and animal materials for the presence of carbohydrates, lipids, and proteins by describing and presenting simple tests in common breakfast food items. (MKR)

Presents activities that use a simple homemade apparatus called "the cannon" to demonstrate Newton's Third Law. Reviews the chemistry concepts behind the ignition of the cannon and presents the Momentum Lab and the Projectile Motion Lab. (JRH)

When students think of evolution, they often think of those genetic changes that occur to make organisms different. This article describes how students can become better informed of convergent evolution, the process by which organisms with dissimilar ancestors come to resemble each other. (ZWH)

Describes an inexpensive, easily prepared demonstration to teach the concepts of human blood grouping, antigen-antibody reactions, and medical transfusions. (ZWH)

Describes an inexpensive method of measuring energy expenditure during exercise. Presents the materials needed to conduct the experiment, basic principles, procedures, calculation and analysis, and a discussion of results. (ZWH)

Presents a variety of writers who have published books that demonstrate the art of botany. The following sections are included: (1) Herbal; (2) Printed Books; (3) Flowers; (4) British Botany; (5) Printing Advances; and (6) Art and Science. Contains 23 references. (ZWH)

Describes the use of a laser pointer to measure the speed of light by incorporating the phase delay between a modulated split beam of light. (JRH)

Describes a measurement lab that introduces measurement and presents a simple example of how to use error analysis with an obvious illustration of its value. The experiment measures the diameters of pinhole images of the sun and uses them to calculate the heights of the leafy canopy that created the images. (JRH)

Presents a polymerase chain reaction (PCR) laboratory exercise that can be performed by introductory biology students in 1 45- to 55-minute class period. Includes a general description of the polymerase chain reaction, materials needed, procedure, and details of interest to teachers. (JRH)

Describes the construction of a vernier scale made of chart paper that can be used to improve the readability of scales on burettes or graduated cylinders. (JRH)

Bioluminescence transformation experiments show students the excitement and power of recombinant DNA technology. This laboratory experiment utilizes two plasmids of "Vibrio fischeri" in a transformation experiment. (LZ)

Describes a lab designed to analyze the organic compounds found in an ordinary fast-food lunch. (ZWH)

Teachers often use demonstrations to prepare students for a science experiment. This article describes a demonstration method to ensure that students are not supplied with all the answers before the actual experiment and to help them to remain an active part of the science lesson. (ZWH)

Discusses the effects of expectancy on learning in a life science instructional laboratory exercise. Contends that prior knowledge directs the act of observing. Investigates the role of prior conceptions on secondary school students' ability to observe scientific phenomena. (Contains 30 references.) (YDS)

Describes an experiment in which the incubation time to observe denitrification and other processes of the nitrogen cycle is reduced from 7-14 days to 24-48 hours. Presents calculations of processes in the nitrogen cycle in the form of a dichotomous key. (SAH)