This month's cover shows a still image from our lead article, a description of multimedia materials and networked instruction by Stanley Smith and Iris Stovall on page 911. Their system is a state-of-the-art approach to making multimedia lessons, laboratory data, interactive tutorials, and web browsers conveniently available to large numbers of students. Anyone who is setting up a computer room or who wants students to have campus-wide access to computer-based instructional materials will be interested in this paper. Two other state-of-the-art computer-oriented articles are on the pages immediately following. On page 916 David Crouch, Michael Holden, and Cindy Samet report on NSF-supported work that introduces a commercially available molecular modeling package beginning in the second semester of the undergraduate curriculum. Scott Childs and Karl Hagen describe on page 917 a 3-D graphical supplement to inorganic and bioinorganic courses that is also based on molecular-visualization software. The results of this NSF-supported project will be available on CD-ROM. Those who are fans of the World Wide Web will be interested in the description on page 923 of use of the WWW as a research tool by freshman-level students who were assigned to write essays on newsworthy issues of scientific interest.

This month our new section provides a new feature: Chemistry behind the News. This one is on Mad-Cow Disease and begins on page A232. Written by one of our staff, Carol Steinhart, it describes the changes in molecular structure of proteins that allow the disease to propagate. Those interested in high school chemistry should look at Emory Howell's Especially for High School Teachers column on page A224. You will also find commentary on graduate education by Glenn Crosby, as irascible as ever, on page A235. There are three reports on meetings and organizations beginning on page A236. The first, by Carol Chen, Jeanne Dyer, and Patricia Strawbridge, describes a conference on cost-effective, hands-on chemistry. The second, by Sylvia Ware, is an overview of the activities of the professional staff of the ACS Education Division in Washington. The third is about chemistry education at two-year colleges by the Chair of the Committee on Chemistry in the Two-Year College, John Kenkel. On page A234 Paul Schatz provides references to reports about the anticancer agent taxol and several other items of interest that have appeared in Scientific American; and of course there are the usual letters (page A225), reviews (page A240), Editor's Basket (page A247), and Marketplace (page A250).

Edmund Winder, Arthur Ellis, and George Lisensky bring us a plethora of applications of solid-state chemistry on page 940. Generating electricity by heating and cooling a thermoelectric device and the converse process of cooling by direct use of electricity are presented both as interesting demonstrations and in terms of the theory of their operation. Several articles deal with electrochemistry. On page 955 Roger DeKock corrects a common misconception about the variable n in the equation relating electrode potential and free energy change. Pierre Millet displays graphically how the distribution of electric potential varies spatially in solutions in electrochemical cells on page 956, and two laboratory experiments beginning on page 959 deal with using electrochemical data to determine both free energy and enthalpy changes. Alfred Saieed and Keith Davies show how the temperature dependence of the electrode potential can be measured in a cell can be constructed from Beral pipets, and Donald Probst and Giles Henderson report on how a standard physical chemistry experiment can be improved.

Several articles deal with chromatography, beginning on page 974. M. Lederer and E. Leipzig-Pagani show their students that simply measuring an R_f value is insufficient as a means of identifying a substance. Jamil Anwar, Saeed Nagra, and Mehnaz Nagi provide an array of inexpensive ways to do thin-layer chromatography with apparatus appropriate for high schools or developing countries. Josef Krause uses a garbage bag to safely spray visualization reagents without a hood.

Providing an appropriate science background for elementary-school teachers is an important priority, and on page 933 Paul Kelter, Kathleen Jacobitz, Elizabeth Kean, and Aurietha Hoessing report on a chemistry course designed for that purpose. It emphasizes hands-on activities, journaling, teamwork, alternative assessment, interdisciplinary focus, and a high level of interaction. Another article, by Dietmar Kennepohl, on page 938 describes home-study experiments that employ microscale equipment and could be used appropriately in courses for elementary-school teachers (or others, for that matter).

The question of how to improve the retention of minority students is addressed by Qun Lin, Paul Kirsch, and Ralph Turner on page 1003. Their qualitative observations indicated that there might be a higher concentration of conceptual thinkers among the minority population, and they report results of a preliminary study designed to determine whether this was correct. Their study supports efforts to involve more conceptual teaching to make chemistry more attractive.

As usual we offer a wide variety of new approaches to laboratory. Of particular interest is the paper on page 984 by Joyce Powell, Sheryl Tucker, William Acree, Jr., Jennifer Sees, and Lindsey Hall. They describe a system that is inexpensive and safe enough that students can be assigned to design their own experimental procedure. Preliminary work on this experiment was done by Upward-Bound high school students.