Presents the details of a waste treatment experiment that enables students to employ much of the chemistry they have learned in class to solve a real chemical problem. Heightens students' awareness of the potential environmental impact associated with the waste they have generated. Contains 21 references. (JRH)

How log-linear models for multiwave longitudinal data can be used to test hypotheses relating to stagelike relationships between variables is demonstrated using data from research on adolescent cigarette and marijuana experimentation. Results with 2,658 adolescents show that the multiwave analyses allow the testing of several hypotheses. (SLD)

Discusses research in spatial cognition that uses computer-simulated three dimensional environments and evaluates the use of virtual desktop environments by replicating an experiment which was formerly done in a laboratory or real world setting. Investigates the role of landmarks when acquiring route knowledge in a system of paths. (Author/LRW)

Examined the production of crime and justice field experiments in the 1990s through data on criminological experiments funded by the National Institute of Justice from 1991 through 2000. Although funds increased in this period, the number of projects and amount of funds awarded to field experiments declines. Discusses reasons for this finding.…

Discusses ways in which datalogging equipment can enable titration curves to be measured accurately and how computing power can be used to predict the shape of curves. Highlights include sources of error, use of spreadsheets to generate titration curves, titration of a weak acid with a strong alkali, dibasic acids, weak acid and weak base, and…

Presents a laboratory procedure that involves students extracting their own DNA from a single hair follicle, using the polymerase chain reaction (PCR) to amplify a polymorphic locus, performing electrophoresis on the PCR products on an agarose gel, and visualizing the alleles to generate a "DNA fingerprint." Discusses theoretical background,…

Describes an experimental approach to determining the speed of light in water using some simple observations and Fermat's principle. Enables students to integrate mathematical techniques and encourages mathematical exploration in which the students have control over what mathematics and technology to use and when to use them. Presents extensions…

Discusses simple and safe techniques that can be used in the educational laboratory to study hemoglobin. Discusses the spectral properties of hemoglobin, spectral-absorbence curves of oxyhemoglobin and carboxyhemoglobin, tracking the conversion of oxyhemoglobin to methemoglobin, and changing from the oxyhemoglobin to deoxyhemoglobin conformation.…

Describes open-ended experiments with seeds from the common garden radish (Raphanus sativus). The phases of the 5-E learning cycle--Engagement, Exploration, Explanation, Extension, and Evaluation--guide this activity series. (Author/MM)

A low-cost, low-tech colorimeter was constructed from a film canister. The student-constructed colorimeter was used to show the Beer-Lambert relationship between absorbance and concentration and to calculate the value of the molar absorptivity for permanganate at the wavelength emission maximum for an LED. Makes comparisons between this instrument…

Describes an activity designed for secondary school students that explains the global carbon cycle and the production of CO2 through soil respiration. (YDS)

Presents laboratory experiments to demonstrate the pH properties of different buffer solutions. (YDS)

Presents a tobacco haploid experiment in which students learn the cytogenetic technique of metaphase analysis of chromosomes and experience the basic principles of haploidy, diploidy, and polyploidy. (YDS)

If students are restricted to making educational experiments only, they might acquire incorrect ideas concerning the nature and role of the experimental method because the educational experiment differs greatly from the scientific experiment by its tasks, complexity, number and variability of experiments and devices used, measurements, and…

Presents a mystery based on the well-known characters, Sherlock Holmes and Dr. Watson. Emphasizes qualitative inorganic analysis, laboratory observations, and oxidation-reduction processes. (Author/YDS)