Presents an activity in which students use a discovery approach to learn about seed texture, similarities and differences among seeds, and which seeds grow on which trees. (MKR)

Discusses an activity in which computers with color monitors can be used to demonstrate light blending with relative ease. (MKR)

Describes two methods for rearing small aquatic invertebrates using submerged surfaces in an unfiltered current of water where fish are present. Presents suggestions on how to use the invertebrate communities in the classroom. (JRH)

Presents activities that help students distinguish between the beneficial layer of stratospheric ozone and the dangerous ground-level or tropospheric ozone, understand the chemical processes of ozone breakdown in the stratosphere, find the sources of ground-level ozone, and explore the differences in the patterns of ozone concentration over the…

Because of the slow pace of astronomical events, their visibility only at night, and the inability to perform much normal experimental work, there is particular pressure to find justifiable activities for pupils during astronomy lessons. This article is intended to provide direct help to teachers in coping with this problem. (15 references)…

Provides background and instructions for the assembly of a microaquarium, or specimen cell, in which the dynamic world of living microorganisms can be viewed through a microscope overextended periods of time utilizing the simplest of materials in the process. (JJK)

This article describes different techniques used to measure air flow velocity. The two methods used were Crawford's Wastebasket and a video camera. The results were analyzed and compared to the air flow velocity predicted by Bernoulli's principle. (ZWH)

Describes how teachers and students can construct a mass, spring scale, lever, and pulley. (ZWH)

Describes an alternative to studying plant community composition and dynamics. Suggests that teachers and students collect soil samples containing buried seeds (the seed bank), germinate the seeds in the laboratory, and analyze community dynamics through the composition of the seed bank. (ZWH)

Describes an activity that uses a simple classroom experiment to measure the amount of carbon dioxide in air samples. (ZWH)

Discusses the use of a National Energy Foundation (NEF) poster, "Rocks and Minerals and How to Use Them." The poster is designed to increase student awareness of the part that minerals play in their daily lives. Information about the NEF and poster availability is provided. (MDH)

Described is a cooperative content study group approach to learning that minimizes individual student memorization and maximizes student interaction. Directions for preparing instructional materials and implementing cooperative home teams, a sample home team worksheet, sample test and study items, and hints and suggestions are included. (KR)

Heavily ionizing charged particles produce radiation damage tracks in a wide variety of insulating materials. The experimental properties of these tracks and track recorders are described. The mechanisms by which the tracks are produced are discussed. (Author/KR)

A principle is presented to show that, if the time of passage of light is expressible as a function of discrete variables, one may dispense with the more general method of the calculus of variations. The calculus of variations and the alternative are described. The phenomenon of mirage is discussed. (Author/KR)