The significant stages in the development of understanding of the concept of electric charge are discussed. The history is outlined with references to certain important experiments, and suggestions are made for relevant school demonstrations and experiments. (KR)

Discussed is the idea that energy is the cause of change. This idea, going back to early cognitive development, means that the teaching of energy needs to confront how, thermodynamically, people can perform actions. The change in energy caused by differences is emphasized. (KR)

Investigates the use of temperature and light to change the usual intervals for plant germinating, sprouting, and flowering. Provides simple experimental procedures and discussions regarding photoperiodism, forced branching before spring, and various types of seed dormancy, including physical dormancy, physiological dormancy, and double dormancy.…

A student hand-out for a recycling unit defines the terms reduce, recycle, and reuse as they relate to solid waste management. Presents the characteristics of recyclable items such as yard wastes, metals, glass, and paper. Lists organizations through which more information about recycling can be obtained. (MCO)

The population of Gyrinus, the whirligig beetle, is assessed using the Lincoln mark-recapture index. This technique has the advantage of helping the student to understand simple proportion as well as other concepts. (Author)

Discusses how reading children's literature aloud can be used to complement science text information. Lists and annotates intermediate books which contain themes that can be correlated with science concepts. (PRA)

Presents a method of analyzing a classic free-fall demonstration using a computer and an audio digitizer. (ZWH)

The results of a survey sent to members of the National Association of Biology Teachers (NABT) asking what they believed to be the essential topics to be covered in the introductory high school biology course are provided. Interpretations of the data and recommendations are included. (KR)

A workshop that provides instruction about chemistry and physics concepts and about novel hands-on ways to teach the concepts using toys is described. Sample topics by discipline and related toys and a daily workshop schedule are included. The results of formative, summative, and follow-up evaluations are presented. (KR)

The results of an in-depth analysis of the lab activities found in two popular high school biology textbooks are presented. Activities were rated against 24 task categories that parallel skills or behaviors which reflect scientific inquiry, problem-solving skills, manipulative skills, and observational skills. (25 references) (KR)

An activity in which students obtain a growth curve for algae, identify the exponential and linear growth phases, and calculate the parameters which characterize both phases is described. The procedure, a list of required materials, experimental conditions, analytical technique, and a discussion of the interpretations of individual results are…

Presents a first day physics activity having students determine the fine for a speeding ticket if the speeds considered include the earth's rotation and revolution speed, and the movement through the galaxy. (MDH)

Presents a cooperative activity between home and school in which parents and students examine the growth of a variety of bulbs. Bulbs are taken home to sprout and returned to school to monitor their growth. Students gather data, hone observation and graphing skills, and communicate with their parents on the project. (MDH)

The principles of magma addition and liquid layering in magma chambers can be demonstrated by dissolving colored crystals. The concepts of density stratification and apparent lack of mixing of miscible liquids is convincingly illustrated with hydrous solutions at room temperature. The behavior of interstitial liquids in "cumulus" piles…

Demonstrations to help students change their misconceptions about chemical bond breaking are presented. Students' misconceptions about chemical bonds in both biological and chemical systems are discussed. A calculation for the release of energy from respiration is presented. (KR)