Describes a simple time-of-flight experiment using readily available equipment. The method of measuring the speed of light uses a modulated laser and introduces students to some concepts of optics, measurement of very small time intervals, modulation of lasers, waveform generation, fast detectors, and data processing. (Contains 20 references.)…

Describes modifications to an apparatus for measuring the force of an object in circular motion. Explains how to accurately measure rotation rate with the use of a motion detector. (WRM)

Reports on a technique for illustrating the dependence of the rate of reaction on the concentration of the reactants and for determining the order of reaction with respect to each reactant, the overall order of reaction, the reaction rate constant, and the half-life. (WRM)

Describes the operation of the Minolta SPAD-502 Leaf Chlorophyll meter. Presents five sample activities for using this technology in high school or college science classes. (WRM)

Discusses the history of the development of Newton's Law of Cooling. Describes an experiment conducted in the kitchen that is designed to test the rate of cooling of a hot block of iron. Finds that Newton's law does not represent very well the mechanism of heat loss. (Contains over 10 references.) (WRM)

Presents the floral foam activity which explores the relationship between volume and mass. Focuses on helping students to enhance their critical thinking skills. (YDS)

Uses charcoal briquettes, ammonia, water, table salt, and laundry bluing to create white fluffy crystals. Briquettes are placed in a bowl while the remaining ingredients are mixed together and poured over the briquettes. The result is white fluffy crystals forming on top of the charcoal. This experiment dramatizes chemical reactions to…

The author's favorite way to start the new school year is to perform a science demo for students. At the beginning of the period, he discusses the importance of making accurate observations. He tells them that he will perform a short demonstration that they are to carefully watch and then record their observations. They each have a sheet of paper…

A second semester biochemistry laboratory has been implemented as an independent projects course at California State University, Sacramento since 1999. To incorporate aspects of carbohydrate biochemistry, or glycobiology, into our curriculum, projects in lectin isolation and purification were undertaken over the course of two semesters. Through…

This study investigated the influence of sourcing and relatedness on the integration of events embedded in simple stories. Participants read pairs of "breaking news stories" from either 1 or 2 news agencies that were believed to be from the Internet. The stories within each pair were either related by virtue of shared situational dimensions (e.g.,…

This research describes a methodology for applying design- and management-based scaffolding techniques aimed to enhance cooperative behavior. Based on assumptions of how successful online learning groups act together, we developed feedback-based mechanisms that aimed at contributing to group functions of well-being, member support, and productive…

Chromatography is a process by which mixtures can be separated or substances can be purified. Biological and chemical laboratories use many different types of chromatographic processes. For example, the pharmaceutical industry uses chromatographic techniques to purify drugs, medical labs use them to identify blood components such as cholesterol,…

In multiple-cue learning (also known as probabilistic category learning) people acquire information about cue-outcome relations and combine these into predictions or judgments. Previous researchers claimed that people can achieve high levels of performance without explicit knowledge of the task structure or insight into their own judgment…

We present a set-theoretic model of the mental representation of classically quantified sentences (All P are Q, Some P are Q, Some P are not Q, and No P are Q). We take inclusion, exclusion, and their negations to be primitive concepts. We show that although these sentences are known to have a diagrammatic expression (in the form of the Gergonne…

Graduate teaching assistants (TAs) are hired to assume some of the teaching duties in large general chemistry programs. They serve as liaisons between students enrolled in the course and the professor in charge. Being assigned to teach immediately on arrival at graduate school may be overwhelming to novice graduate students. When sending them into…