Describes methods for studying heart primordia of the chick embryo, using the organ culture method. (CS)

Described is a school project to investigate aggregations in flatworms which may be influenced by light intensity, temperature, and some form of chemical stimulus released by already aggregating flatworms. Such investigations could be adopted to suit many educational levels of science laboratory activities. (DS)

Two implanted slide techniques are described by which activity of proteolylic bacteria and the growth of algae in the soil can be readily studied by school students using simple apparatus and methods. Variations are suggested for studying the effects of agricultural practices and environmental conditions on the soil bacteria and algae. (Author/DS)

Describes a method to determine the thermal diffusivity of a polymer, which is suitable for the undergraduate laboratory. It serves as a practical demonstration of classical Fourier theory. (Author/HM)

Provides a list of the reactions commonly used for introductory kinetics studies. These reactions illustrate the kinetics concepts of rate law, rate constant, and reaction order. Describes a kinetic study of the hydrolysis of 3-bromo-3-phenylpropanoic acid which offers many educational advantages. (CS)

Activities and experiments are suggested for teachers who wish to introduce their students to the idea of "change." The activities are those which are common in many early childhood situations. (SA)

Activities and experiments with leaves are given for use with elementary students. Classifying and measuring are ideas which are suggested for involving children in some in-depth projects with leaves. (SA)

Describes the method to use in collecting freshwater algae for study in the classroom. Equipment lists are given as well as several illustrations. (SA)

Demonstrations involving foods that illustrate chemical concepts are described, including vaporization of liquids and Graham's law of diffusion, chemical reaction rates, adsorption, properties of solutions, colloidal dispersions, suspensions, and hydrogen ion concentration. (CS)

The theoretical basis for the calculation of hydration numbers is developed. (BB)

Describes a simple experimental system whereby the comparative actions of long, medium, and short-acting barbiturates can be demonstrated in a relatively short period of time under optical microscopy using pollen grains as the biological test or assay system. (Author/HM)

Describes an improved experiment of the thermal dehydration of copper (II) sulfate pentahydrate. The improvements described here are control of the temperature environment and a quantitative study of the decomposition reaction to a thermally stable oxide. Data will suffice to show sequential gravimetric analysis. (Author/SA)

Unusual experiments in sound are described. Sounds produced from the vibration of areas are represented by many beautiful sand patterns. The vibrating areas vary from square to circular plates. (SA)

Simple laboratory investigations are given which expose elementary students to optical crystallography techniques. Procedures and materials are designed for sixth-grade students. (SA)

The laboratory experiment described here is intended to be of use to the forensic science major enrolled in a course in organic chemistry. The experiment is the use of thin-layer chromotography for qualitative analysis, specifically for the identification of drugs. (Author/SA)