From the time they are born, children have a natural curiosity toward the world around them. Even though they can't speak, one can still observe that they are skilled at discovery. Science fair projects can nurture this natural curiosity and give elementary students the opportunity to explore their interests in a rewarding way. Participation in a…

The instructional design and the corresponding research on student learning of two virtual laboratories that provide an engineering task situated in an industrial context are described. In this problem-based learning environment, data are generated dynamically based on each student team's distinct choices of reactor parameters and measurements.…

Based on a three-year-long ethnography of the hobby of model rocketry, I present a practice-centered theory of interest relationships--that is, the pattern of long-term, self-motivated engagement in open-ended practices that has been theorized under the concept of "individual interests". In contrast to extant theories of individual interests, in…

This paper describes an enjoyable, simple, and inexpensive way to perform Young's two-source experiment using sound waves. The wave source is a simple aluminum rod (a "singing rod").

The similar mathematical forms of Coulomb's law and Newton's law of gravitation suggest that two uniformly charged spheres should be able to orbit each other just as two uniform spheres of mass are known to do. In this paper we describe an experiment that we performed to demonstrate such an orbit. This is the first published account of a…

Terms to be familiar with before you start to solve the test: cytokines, cytokine receptors, cDNA library, cDNA synthesis, poly(A)[superscript +] RNA, primer, template, reverse transcriptase, restriction endonucleases, cohesive ends, expression vector, promoter, Shine-Dalgarno sequence, poly(A) signal, DNA helicase, DNA ligase, topoisomerases,…

Two students, meeting together with a teacher, redid historical experiments. Unlike conventional instruction where science topics and practices often fragment, they experienced interrelatedness among phenomena, participants' actions, and history. This study narrates actions that fostered an interrelated view. One action involved opening up…

A simple experiment about thermal effects in chemical reactors is described, which can be used to illustrate chemical reactor models, the determination and validation of their parameters, and some simple principles of heat transfer and sensor dynamics. It is based in the exothermic reaction between aqueous solutions of sodium thiosulfate and…

The generally accepted method to determine iron content in food is by acid digestion or dry ashing and subsequent flame atomic absorption spectrometry or inductively coupled plasma atomic emission spectrometry. We have developed an experiment that chemically extracts the iron from an egg yolk and quantifies it using UV-vis absorption…

Diapocynin (5,5'-dehydrodiacetovanillone) was synthesized by oxidative coupling of apocynin (acetovanillone, or 4-hydroxy-3-methoxyacetophenone). Diapocynin is a metabolite of apocynin, which has anti-inflammatory and anti-oxidative properties. The oxidizing agent was an in situ generated sulfate radical, produced by adding iron(II) sulfate and…

In this article I review one of the most significant accomplishments of Frank H. Westheimer, one of the most respected chemists of the 20th century. This accomplishment was a series of stereospecific enzymatic oxidation and reduction experiments that led chemists to recognize what we now call the enantiotopic and diastereotopic relationships of…

Plant-derived phenolic compounds such as those found in red wine, tea, and certain fruit juices may protect against cardiovascular disease by detoxifying (scavenging) superoxide and other unstable reactive oxygen species. We present a laboratory exercise that can be used to assess the superoxide-scavenging capacity of beverages. Among the…

An experiment and a demonstration concerning transport by magnetic levitation (Maglev) are described. The lift, drag and radial forces on a magnet placed over a rotating conducting disc are measured versus the rotation frequency. The experiment relates to important topics of electromagnetism and could be a useful addition to the undergraduate…

In this paper, we report the development of an automated system for energy bandgap and resistivity measurement of a semiconductor sample using Four-Probe method for use in the undergraduate laboratory of Physics and Electronics students. The automated data acquisition and analysis system has been developed using National Instruments USB-6008 DAQ…

Preservice elementary education students often do not have a good feel for the process of science. Many may be acquainted with the steps of the scientific method but have never been through the scientific process. An exercise was designed using temperature-logging iButtons (Thermochrons) to improve knowledge of and familiarity with the process of…