Describes a technique for comparing the number of bacteria in various soil samples. The equipment and materials are readily available, and the technique is suitable for high school students. (JR)

Summarizes the thermodynamics of macromolecular systems, including theories and experiments of cyclic energy conversion with rubber and collagen as working substances. Indicates that an early introduction into the concept of chemical potential and solution thermodynamics is made possible through the study of the cyclic processes. (CC)

Describes a method for measuring osmotic potential which is suitable for high school and college biology classes. This method introduces students to the hard-to-visualize technique of using density gradients to separate cells or cell constituents of differing densities. (JR)

Describes two experiments in physiology using a readily available marine vertebrate, the flounder. Representative results are presented from experiments which measure the effect of excess potassium on the flounder EKG, and the effect of temperature on heart rate of the starry flounder. (JR)

Describes simple quantitative determinations for ethanol and carbon dioxide, together with techniques for examining the effects of a number of environmental factors on their production. The experimental work centers around the growth of a cell population of yeast, and is suitable for senior high school students. (JR)

Describes two experiments using carbon dioxide cartridges to demonstrate Newton's third law of motion. (JR)

Discusses an open-ended experiment which is instigated by students to study noise levels on the Kent State University campus. Indicates that the activities make it possible for the students to acquire socially relevant and potentially useful information under more realistic environments. (CC)

Discusses various ways established by the Task Group on Education in Astronomy, including publication of teaching resources and lists of speakers for teachers' meetings at all levels and of writers of articles for teachers' journals. (CC)

Discusses the use of a balance assembled from standard laboratory components to conduct an experiment on the repulsion between two bar magnets. Includes an analysis of data on the two-pole and four-pole models. (CC)

Describes some laboratory experiments that can strengthen the study of non-aqueous ionizing solvents in Nuffield A-level chemistry course. (PS)

Research supported by a grant from the National Institute of Mental Health. (VM)

Research supported in part by a graduate traineeship from the National Institute of General Medical Sciences to the author and by a grant from the Advanced Research Project Agency to the Harvard University Center for Cognitive Studies. (VM)

Includes thirteen topics relating to laboratory activities, organisms, and teaching materials for secondary school biology classes. Also provides a reading list of articles published during 1972 that are suitable for A and S level biology. (JR)