Discusses the use of an overhead projector for the deflection of a vertical image to a screen. Describes three demonstrations: magnetizing of a steel ball bearing and paper clip; convection currents of a hot liquid within a cold liquid; and oscillation of concentrated salt solution into fresh water. (YP)

Described is a technique for taking a large monolith for the purpose of teaching soil structure. Materials and procedures are detailed. A survey of 93 students indicated that the larger monolith was preferred over the commonly used narrow ones. (CW)

Describes making a cardboard frog. Discusses the physics of various motions of the frog. Provides diagrams showing how to make the frog, the motions, and the mechanics formulas. (YP)

Describes the use of the polygenic trait of total fingerprint ridge count in the classroom as a laboratory investigation. Presents information on background of topic, fingerprint patterns which are classified into three major groups, ridge count, the inheritance model, and activities. Includes an example data sheet format for fingerprints. (RT)

Cites beach debris projects implemented by the states of Oregon, Texas, and North Carolina. Credits the success of Beach Sweep '88 to the establishment of five primary goals, the zone captain strategy, and the use of data cards. Provides an example data card, classroom activities, and alternatives to balloon launches. (RT)

Explains a lesson in which the scientific method is used as a teaching strategy. Discusses when this approach can be used, the interdisciplinary method, and sample science concepts that can be appropriately taught this way. (RT)

Explains the development of a science program which was initiated to help students, parents, and other teachers appreciate science. Provides a list of materials needed, procedures, questions, and objectives for performing two of the 30 activities used in the project. (RT)

Explains a state standardized science program evaluation system that includes hands-on activities. Explains the syllabus, workshops, purpose of test, test features and its component parts including sample questions. (RT)

Demonstrates a variety of electrical phenomena to help explain atomic structure. Topics include: establishing electrical properties, electrochemistry, and electrostatic charges. Recommends demonstration equipment needed and an explanation of each. (MVL)

Describes two demonstrations (1) a dust explosion using a coffee can, candle, rubber tubing, and cornstarch and (2) forming a silicate-polyvinyl alcohol polymer which can be pressed into plastic sheets or molded. Gives specific instructions. (MVL)

Uses paper chromatography with food dyes to provide a simple and inexpensive basis for teaching chromatography. Provides experimental methodology and tabled results. Includes a solvent system comparison (Rf) for seven dyes and twenty-two solvents. (MVL)

Describes a teaching exercise used to demonstrate the importance of context in studying the ecology of animals. Uses the game of chess to examine the relationship between information and context and as an analogy with ecology. Discusses procedures, examples of results, and insights gained from this activity. (CW)

Reviews a software package, "Mitosis-Meiosis," available for Apple II or IBM computers with colorgraphics capabilities. Describes the documentation, presentation and flexibility of the program. Rates the program based on graphics and usability in a biology classroom. (CW)

Presents an algorithm for solving problems related to multiple allelic frequencies in populations at equilibrium. Considers sample problems and provides their solution using this tabular algorithm. (CW)

This article presents a variety of topics discussed in this column and at a biology teachers' workshop concerning the quality and value of lab techniques used for teaching high school biology. Topics included are Drosophila salivary glands, sea urchins, innovations, dyes and networking. (CW)