Outlines the discovery and nature of ultraviolet light, discusses some applications for these wavelengths, and describes a number of experiments with ultraviolet radiation suitable for secondary school science classes. (JR)

Describes how the continuous variation method may be used in senior chemistry classes at the secondary level. This technique allows for the detection of the one or more reactions that may occur in a system over a wide range of composition. (JR)

Discusses the use of programmed scripts, textbooks, films, and cassette tapes to conduct a self-instruction laboratory course. Indicates the presence of marked positive effects on the development of the students' ability to plan their own experiments. (CC)

Discusses three experiments, respectively, relating to electricity, optics, and electronics, which provide both the experienced and weaker students with a high interest in determining unknowns from a limited amount of information. (CC)

Presents an outline of current knowledge relating to the response of radicles to a directional source of water (hydrotropism). New techniques are described that may be used in biology classes to demonstrate the hydrotropic response in plants. (JR)

Outlines the advantages of using the readily available eggs of the nematode Rhabditis in studying the early cleavage stages of animal development. Discusses the identification and life history of Rhabditis, how to culture and examine the organism, the cleavage stages and cell lineage, and sources of visual aids. (JR)