Our cover highlights the nitrogen cycle and fixation of nitrogen by lightninga major process in the atmospheric environment. This month we have something about almost every aspect of chemistry and the environment: air and water pollution, toxic-substance control, interdisciplinary courses, and student research projects. We hope that out of these riches you will find a number of things that you can incorporate into your teaching.

Randall, page 1409 *, provides a graphic and very readable description of the benefits to high school students of participating in field work on stream testing. Concepts that in the classroom are somewhat esoteric become much more concrete and better understood when students are knee deep in cold water. Ottewill and Walsh, page 1426 *, describe a group project in which students act as consultants to a small electroplating company regarding removal of metal ions from wastewater. Weidenhamer, page 1437, has changed a quantitative analysis laboratory into a project-oriented format that concentrates on environmental analyses. Halstead, page 1390 *, reporting on the Council on Undergraduate Research meeting, describes an undergraduate research project that involves investigating environmental systems.

Driscoll, page 1424 *, describes a demonstration (checked by Jones) that clearly shows formation of nitrogen oxides during high-temperature combustion in air. His paper also provides useful information about the concentrations of nitrogen oxides as a function of temperature. Allen, Brauers, and Finlayson-Pitts, page 1459, show how atmospheric pollutants can be measured in an instrumental analysis laboratory using differential optical absorption spectrometry.

This month's JCE Classroom Activity, page 1456A *, shows how swimming-pool kits can be used to carry out simple water analyses and obtain useful information about the environment. Other similar analyses are available on the Web through the GLOBE project; see Judd, page 1394 *, News from Online. Try some of these Web sites! In the Secondary School Section Kelter et al., page 1413 *, provide an overview of water pollution, describe its impact on health, contrast effects in the U.S. and in Mexico, describe state-of-the-art methods for analysis of three typical pollutants, and provide analyses suitable for use in high school courses. Yappert and DuPré, page 1422 *, have devised an overhead projector demonstration of an EDTA titration to determine water hardness. Klausen, Meier, and Schwarzenbach, page 1440, describe a laboratory in which kinetics of hydrolysis of 2,4-dinitrophenyl­acetate serves as a model of decomposition of compounds in the environment. Another kinetics experiment, by Duong, Penrod, and Grant, page 1451, allows students to study a bio­remediation process, degradation of p-nitrophenol by the bacterial strain Pseudomonas sp. Bowers et al., page 1455, show that dissolution of carbon dioxide in water can be considered a relaxation process and describe an experiment by which forward and reverse rate constants can be determined. Herrer-Mellián et al., page 1444, report a voltammetric determination of nickel and cobalt in water samples.

Jansen, page 1411 *, has helped create and teach an interdisciplinary course that brings to elementary education majors field and laboratory experiences in chemistry, geology, and physics. Juhl, Yearsley, and Silva, page 1431, have combined a chemical technician course and an environmental technician course to create opportunities for students from both areas to participate in an environmental water quality study.

Tomboulian and Parrot, page 1434, describe a program for environmental health majors that provides a strong science-based technical background with critical thinking skills. Casparian, page 1402 *, has reviewed a videotape that deals with agricultural biotechnology and brings to the classroom a broad range of views on this controversial subject. Orbell et al., page 1446, have developed an interesting way to demonstrate remediation of oil spills by absorbing the oil on polymer-coated iron beads and recovering the beads magnetically. Ibanez et al., page 1449, have developed a microscale laboratory in which organic wastes are destroyed by indirect electrolysis.

It has been only a little over 50 years since observation of the first NMR signal was reported independently in January 1946 by Bloch at Stanford and Purcell at Harvard, but what advances have been made in those years! Beginning on page 1468 and continuing through page 1490, this issue provides five laboratory experiments involving NMR, a general method for calculating proton chemical shifts for methyl, methylene, and methine protons, a discussion of spin-spin coupling in ¹³C NMR, and a compilation of educational NMR software. Those celebrating 50 years of NMR, those who use NMR as a tool, and many others will find much useful information here.

We don't publish many presidential speeches, but there is one this month in our report from 2YC₃. On page 1392 *, readers will find a summary of Clinton's strong commitments to education in general and to making 14 years of education universal via two-year colleges.