Provided are two experiments which deal with the formation of callus and embryos from tissue culture of carrot roots. Outlined are the purpose, materials, procedure, and results for each. (RT)

Several modifications that improve upon the assay of photosynthesis are suggested. Described are the apparatus, materials, light intensity and photosynthesis measurements, and results. A table of the average light intensity values versus the screen number and a sketch of the experimental set-up is included. (RT)

Introduces an experiment involving the observation of Brownian motion for college students. Describes the apparatus, experimental procedures, data analysis and results, and error analysis. Lists experimental techniques used in the experiment. Provides a circuit diagram, typical data, and graphs. (YP)

Describes "Parents and Children for Terrific Science (PACTS)" program sponsored by the American Chemical Society's Education Division for encouraging the development of family science projects at the elementary and intermediate school levels. Discusses some examples and the results of the project. (YP)

Students use their preschool experiences to form personal theories about the world and rarely correct misconceptions even when new information is presented. This article describes an elementary science teacher's efforts to help fifth and sixth graders revise personal electricity theories, based on experimentation. There is no simple way to…

Presents a distillation experiment that uses temperature sensors connected to a computer in place of thermometers, and enables the whole class to view the data on a monitor and interpret and discuss the data in real time. (JRH)

Presents authentic assessment laboratory activities in which students measure the amount of sugar in bubble gum and test the lasting power of soap bubbles. Includes scoring rubrics. (MKR)

Describes the Packard's Falling Body Apparatus, invented by John C. Packard, which is essentially an inclined plane combined with a simple and elegant method of measuring the relative time of descent of a steel ball. (JRH)

Lists suggestions for improving experiments involving effects of various chemicals on Daphnia heart rate. Concludes that the real value of these experiments lies in what they teach about variations in the response of living things to chemicals and the difficulties researchers encounter when doing experiments with living things. (JRH)

Describes an experiment to investigate chemical changes, pH, dissolved oxygen content, light intensity, and temperature in water containing aquatic plants. (MKR)

Presents an exercise that gives students a real feeling for experimental errors and demonstrates the importance of frequent repetition and averaging. (JRH)

Describes the activities of the kNights of Physics, a group of preservice teachers, whose goal is to spread the knowledge of the fun of physics to elementary students and their parents. (JRH)

Describes a system that demonstrates how a color may be generated and specified in mathematical terms. Illustrates the mixing of primary colors as well as the concepts of saturation, luminance, and illumination. (JRH)