The PSNS project - Journal of Chemical Education (ACS Publications)

The PSNS project. Elizabeth A. Wood. J. Chem. Educ. , 1969, 46 (2), p 69. DOI: 10.1021/ed046p69. Publication Date: February 1969 ...
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Elizabeth A. Wood

37 Pine Court New Providence, New Jersey 07974

It was in April of 1965 that the PSNS Project was born, with the Advisory Council on College Chemistry and the Commission on College Physics acting as midwives. PSNS stands for Physical Science for Nonscience Students and the goal of the project was to produce a new one-year college course in Physical Science designed especially for those students who were not majoring in science. The project was funded entirely by the National Science Foundation. The co-directors of the project are Professor Lewis G. Bassett of the Chemistry Department of Rensselaer Polytechnic Institute, at Troy, New York, and Prof. Walter E. Eppenstein, of the Physics Department. Professor Arnold A. Strassenburg of SUNY at Stonybrook is an Associate Director and Chairman of the Advisory Board. The other Associate Directors are Professor Robert L. Sells of the State University College at Geneseo, New York, and Elizabeth A. Wood, formerly with Bell Telephone Laboratories. During the summer of 1965 an exceptionally harmonious group of chemists and physicists, all college teachers, worked together as a designing and writing team at Rensselaer Polytechnic Institute. Seven of them and one outsider tried the course the following winter. During the summers of 1966 and 1967 the materials were revised as a result of feedback from course trials. Twenty-three colleges used the course in 1966-67 and thirty-eight in 1967-68. The "third preliminary edition" of the text was printed this year by John Wiley who will publish the "final edition" in the summer of 1969. The text contains questions and problems appropriate to each chapter and carefully chosen reading selections (not just a list of books) pertinent to the various topics of the course. In addition there is a Teachers' Resource Book, thicker than the text, with answers to all the questions, more questions for use on homework and examinations, useful laboratory advice, and background enrichment. Schools that have a physical science course for nonmajors that is satisfactory are in a minority. The students taking the one-year physical science course are, in most cases, reluctantly taking it to fulfill a requirement. Their contact with science in high school has been an unhappy experience and they dread a repetition of that experience. In many colleges such students are subjected to a condensed version of beginning physics, given in one semester by a member of the Physic Department who didn't want to give it, and a totally separate semester of chemistry, given under similar circumstances. These courses, similar to those which gave the students their distaste for physical science, but faster in pace, are likely to leave them behind from the start and deepen their antagonism. Contrary to the opinion in many college science

The PSNS Project

departments, we of PSNS feel that these students are worthy of our best effork in their behalf. Commonly more than half of them will be elementary school teachers, with the power to influence profoundly the attitude toward science of the coming generation. How easily their dislike of a subject is absorbed by their students! The rest of the physical science class is made up of those who will have a smaller, but not inconsiderable, influence: our future lauyers, authors, bankers, artists, and congressmen. To all of these we would like to bring the personal enrichment that comes from enjoying physical science. We have them for one valuable year. We know that we will lose them if we try to pack a lot of information into that year. What has to be done during the only chance we have? Our most important task is to change their feeling of confusion and antagonism into one of confidence and interest in physical science; to show that the essence of science is observation and wondering and trying to find out about the physical world, not memorizing answers. To achieve this, they must make their own observations, form and test their own hypotheses. The PSNS course is not a course about science; it is not a survey course of facts someone else has found out; it is primarily a course to give the students the feel of doing science. Hopefully the elementary school teacher who has been through PSNS will feel confident that she is doing a good job when she encourages the natural curiosity of the children, rather than feeling a sense of panic because she cannot answer their questions about nuclear fission. We have chosen to approach their experience in physical science through the study of solid matter, how it got that way, how it behaves when you do things to it, and how to find out about it. This is a vertical approach, beginning with the tangible investigation of familiar substances in simple Tvays and gradually deepening our study through the course as the students become ready for more sophisticated experiments and discussion. The text is entitled "An Approach to Physical Science." The students are repeatedly reminded that i t is not the only approach. I t is obvious that solids belong to both chemistry and physics and it was this joint ownership of much of the subject matter related to the nature of solids that further made this area attractive as the focus of an integrated physical science course. But the focus is not so sharp as to exclude things that would be useful in learning about solids. What heat does to solids leads to liquids. The easiest way to open the eyes to thermal motion in solids is through studying the behavior of gases. In order to think clearly about the forces that hold solids together some elementary mechanics and some experiments in electrolysis are needed. Each of these is taken Volume 46, Number 2, February 1969

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up only when the need to know about it can be made clear to the student. Real scientific investigation has all the fun of a treasure hunt or a mystery story. A person follows up clues with enthusiasm because he needs to know what they can tell him. How dull it would be if he were given all the answers first and then allowed to read an account of the hunt or trial as an illustration of what he already knows. Experiments should precede the discussion of them, not follow it. "Something is happening! What goes on here?" Let's have surprises that stimulate inquiry, not demonstrations after explanations that have made inquiry unnecessary. I n PSNS we have tried to have experiments and observations come first and time is allowed for interpretation of the results by the students. I n some cases, as in any scientific laboratory, a problem is put on the shelf for a while To have questions in the back of one's mind, nagging gently for an answer, is an experience familiar to any research scientist. Later, when the student comes upon something that makes contact with that question in the back of his mind, there is that satisfying sense of seeing the parts fit together to make a reasonable whole that is one of the rich rewards of scientific work. This is not the fastest way of getting some particular relationship into a student's head, but it is the only way in which he can understand how we know what we know about the world around us. To make time for this important process we have eliminated much that is taught in survey courses. We have produced a few supplementary chapters for those teachers who have four lecture hours a week plus laboratory time. There is one entitled Acids and Bmes; one on magnetism; one on rocks and minerals, called Matter in the Earth; and one called Matter in the Astronomical Realm. Others are contemplated, but we are concerned about the possibility that zealous teachers will start filling the time too full of subject matter again, moving too fast for these students for whom the ways of science are strange and difficult, building again that wall of antagonism that we have worked so hard to tear down. Experiments are an integral part of the course. There is not a separate laboratory manual. Descriptions of experiments occur right in the text as need arises for them. The equipment is simple. It is currently most conveniently obtained by ordering it through Wiley. We had originally hoped to have only experiments that one could perform in a dormitory room, but found that even such heat sources as an alcohol lamp or a baby's bottle-warmer were prohibited in dormitories. Some can still be done at home and there is a big advantage in having the student do them there where he can play with them at leisure if they begin to catch his interest and can come back to them again and again, asking himself, "What goes on here?" It is particularly important for these one-year students to become aware that physical science is not just something that happens in the laboratory, but that it relates to common experiences, so that such experiences will furnish reinforcement in years to come and

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Journal of Chemicol Educoiion

their enjoyment of physical science will be a lasting one. Consider, for example, the common test for a hot iron for pressing clothes. When the spit on the finger hisses in contact with the iron, what goes on here? What is the maximum amount of information this gives you? Or again: we can cool something by blowing on it or we can warm something by blowing 011 it, simply by shaping the opening of the mouth differently. What goes on here? I n addition to the feel of doing science, there were certain principles and aspects of science which we felt should run throughout the course as threads woven into the subject matter and noticed from time to time: the conservation principles; the beauty of the self-consistency of science--the way it all fits together; symmetry; and the clear simplicity of a statement that is provided by a mathematical expression. This last we had to creep up on very gradually with a great many words preceding even the simplest expression. We knew, from a preliminary test, that, although most of these students could handle 4X = 8, few could solve the equation l/X = 8. The text alone cannot teach the course planned. The teacher is the most important single factor in its success. A teacher institute was held a t Rensselaer Polytechnic Institute the summers of 1967 and 1968. About half the time was spent enriching the chemistry background of those trained in physics and the physics background of those trained in chemistry. The course should be taught by a single instructor who sees it as an intimately-connected whole and doesn't try to separate it artificially into parts with familiar labels. We have engaged the services of ETS, the Educational Testing Service, to suggest a program of objective evaluation of our results and they have done this, but have cautioned against putting too much reliance on the results of such tests since change of attitude and potential for continued interest in a subject are very difficult to test for. They have suggested that a good way to evaluate the results would be simply to question the teachers and students about the successof thecourse in achieving its goals. We have solicited and received a great deal of feedback from teachers and students. I t seems to have a normal distribution. A few think the course too easy and too slow. These are usually students who have done well in a good high school physics or chemistry course and are writing their complaints during the early stages of the course where we are purposely proceeding sloudy to gain the confidence of those who have never beeu able to keep up with a science course. A few think the course too difficult and one complained of the "Einsteinian" mathematics involved. But many encouraging letters from both teachers and students indicate that the pace and level and content are such as to give to a large part of the group for whom it was designed a sense of achievement and interest in science that has never beeu felt before. When we started work nearly four years ago this is what we hoped to accomplish.