This paper describes the Scientific Tools and Techniques course for ninth grade students in the Dekalb County, Georgia, public high schools. The course is offered at the Fernbank Science Center, a magnet school owned by the Dekalb County Schools and Fernbank Incorporated and operated by the school system. Investigations are described in the…

Presents investigations to explore the substrate specificity, pH, concentration, and temperature relations of an enzyme with only inexpensive commercial rennet and basic laboratory equipment. Describes how the activities were carried out with a group of 15-year-old students. (CW)

Differentiates the tricarboxylic acid (TCA) cycle (or Krebs cycle) from glycolysis, and describes the bridge between the two as being the conversion of pyruvate into acetyl coenzyme A. Discusses the eight steps in the TCA cycle, the results of isotopic labeling experiments, and the net effects of the TCA cycle. (TW)

Reported is a method of producing artificial lightning in an ordinary clear lightbulb. The appearance of sparks produced is that of a miniature stroke of forked lightning seen in natural thunderstorms. The sparks also show the intricate branching patterns often seen in natural lightning. (JT)

Presents a laboratory exercise on photosynthesis suitable for high school biology. Allows students to perform the experiments with easily obtainable materials and within a lengthened period. Includes photosynthesis lab prep notes for teachers. (JRH)

Presents an experimental approach to illustrate that the thermodynamic properties of a system can be considered as the average of mechanical variables. Discusses the Knudsen effusion method to count the number of molecules, vapor pressure, the piezoelectric effect, the experimental setup, and sample experimental results. (JRH)

Presents an activity to determine whether the radioactivity of a pure potassium salt is directly proportional to the amount of potassium in it and whether this could be used as a method of analysis for potassium in a solid. (MKR)

Describes a laboratory exercise used by botany students to verify their textbook's teaching about photosynthesis and respiration. (ZWH)

Describes an inexpensive replacement for the gel matrix, agarose, to aid teachers in reducing the cost of supplies needed to perform gel electrophoresis experiments. (ZWH)

Describes a simple way for groups to view a demonstration of Brownian Motion using a laser and liquid suspension. (AIM)

Discusses the behavior of the current near the end of the paper in the electric-field mapping experiment and approaches to solving problems associated with this behavior. Presents programs that can be used to model the boundary condition computationally. (JRH)

Describes an experiment to measure the speed of air in the air jet caused by blowing air through a drinking straw. (JRH)

Describes a diffraction experiment that uses circular holes salvaged from nonaerosol hair spray bottles to produce spectacular circular interference fringes. (JRH)

Presents a model experiment for quantifying phagocytosis using earthworm coelomocytes and determining the optimum length of time necessary to obtain maximum phagocytosis. Involves incubating coelomocytes from invertebrates with an antigen, staining the cells, counting the number of antigen particles ingested, and measuring the effect of different…

Describes the preparation of a simple microbiological medium using inexpensive materials routinely available in any supermarket. Discusses inoculation of the medium and colony examination. (JRH)