This issue's cover shows the B-Z reaction occurring in a petri dish. This is one frame from a video sequence on the ChemDemos II videodisc, this month's offering from JCE: Software (page 874). The B-Z reaction also features in the article by Omar Benini et. al. on page 865. They have taken this popular demonstration and transformed it into a laboratory experience that involves students in chemical kinetics and numerical integration for data analysis. On page 868 Peter Strizhak and Michael Menzinger develop the principles that underlie the B-Z and other oscillating reactions, a contribution that nicely complements the paper that precedes it.

Chemical Eduacation Today

This new section of the Journal premieres with this issue. It brings you news and commentary, reports from associations, letters to the editor, award addresses, and other timely material invited by the editor. Of particular interest this month is the address given by Nobel Laureate Roald Hoffmann upon his receipt of the ACS George C. Pimentel Award in Chemical Education Sponsored by the Union Carbide Corporation (page A202).

Also in Chemical Education Today are commentaries by Richard N. Zare (page A198) on chemistry in science museums and by Glenn A. Crosby (page A200) on the National Science Education Standards. A review of reviews of books about Linus Pauling appears on page A 210, summaries of interesting papers from other journals and the internet begin on page A191, and Jerry Bell's report from AAAS is on page A196. Lots of interesting reading, if only you can get to it before classes begin!

Cooperative Learning

Our two lead articles in this issue both deal with cooperative learning - classes that focus squarely on the students, making them much more responsible for their own learning. John C. Wright (page 827) describes a one-semester introductory analytical course that uses open-ended laboratories, cooperative learning, student-generated spreadsheet models, and readings from the research literature to help students become much more independent learners.

In the next paper (page 832) Richard M. Felder, a chemical engineer, describes what he calls "active-inductive-cooperative learning" and describes its effectiveness in a five-semester sequence of courses. The evidence is that this approach can address different learning styles and works very well. The author challenges us chemists to adopt similar approaches in our courses.

Colloids and Micelles

Several papers this month deal with colloids, emulsions, and micelles. John W. Hill (page 847) describes an excellent analogy between the behavior of musk oxen and that of surfactant molecules. Many common foods consist of emulsions. Carlos Bravo-Diaz and Elisa Gonzales-Romero (page 844) describe several interesting experiments that use such foods as their principal reagents. Kitchen chemistry such as this can be effective in convincing students that chemistry is not confined to books, problems, or labs.

Quentin R. Peterson (page 848) has discovered that a simple centrifuge from a qual analysis lab provides an excellent means of separating milk curds and whey in preparation for a standard introductory experiment. Steven J. Bachofer describes how to use conductivity measurements to characterize micellar solutions on page 861. And on page 889 Bert O. Haglund et. al. describe the theory and measurement of diffusion of rhodamine-B into hydrogels.

Laboratory

In addition to a number of excellent experiments, this issue contains several papers that deal with computers in the laboratory. On page 876 William J. Treadway, Jr. reports on a multimedia chemistry laboratory that is more successful with students than the real thing. On page 878 Bradley J. Hernlem describes a versatile and inexpensive automated titration device, and on page 881 Kuruppu A. N. Dharmasiri et. al. explain how they used a personal computer to resurrect a mass spectrometer whose data station was obsolete, unreliable, and impossible to service.

Meet Your Journal's New Staff

Pages A186 and A187 introduce the new Journal staff in Madison and our soon-to-be Secondary School Editor, Emory Howell. The staff look forward to serving you every month with an interesting and useful collection of articles and ideas for your classroom and laboratory.