George W. Stapleton Arcadia High School Arcadia. California 91008
Reflections of a High School Teacher Dimensions and experiences
"What is life hut a series of inspired follies? The difficulty is to find them to do. Never lose a chance: it doesn't come everyday." Today, I would relate George BernardShaw's comment to the all too human enterprise called science, where the best accomplishments involve people interacting with the tangible and imagined world ahout them as well as with other people, where the inspired follies of scientific discouerv occur for all aees. The kindergarten teacher may he inte;acting with a fi;e-year-old in the process of discovery, or a eraduate student may he interacting with his advisor as t h i y map out the research necessary for completing the PhD. Human involvement and positive interaction are the important keys to a successful learning experience a t any level of cognitive human development. A necessary catalyst to the learning process, however, is concern. Interaction without concern creates a learning situation that is essentially sterile. As I share with you the reflections of one high school chemistry teacher, may I emphasize my own position by predicating my beliefs about teaching and about learning on genuine concern for the subject and even greater concern for the individual. With this preface I would like to share some ideas with you. First, I would like to explore the dimensional aspect of the chemistry teacher's reflections, that is, the various ways that the high school chemistry teacher may hecome more involved, ways he may he used more effectively. Second, I would like to suggest the kinds of experiences that a chemistry teacher can create to inspire our young people with the fascinating world of chemistry, hoth a science and an art. Challenges for the Chemistry Teacher for the Seventies Traditionally the high school chemistry teacher has been assigned to one plant where he meets his classes five days a week for aooroximatelv an hour a day. This orocedure, of course, n o t only limits his effectiveness in the teaching process. hut also orecludes the oossihilitv of making maximum some use bf his skiils and talents-. I would like to alternatives. Instead of meeting five groups of students each day, the chemistry teacher should meet with three, the remainder of his time to he spent in a different capacity. He should spend time in interaction with students and teachers a t all levels of the education system to provide greater articulation for the science program and optimal use of the chemistry teacher. A primary rationale for such articulation stems from the fact that a student in his first high school chemistry class must use numerous skills and talents that should have been acquired in other courses. Success in chemistry requires skill in arithmetic, in reading, and in an involved process termed the ability to make intelligent choices. For the high school chemistry program to survive, some changes are imperative and these changes must include the use of the teacher as a resource person as School in Arcadia, California is the recipient of the 1975 James Bryant Conant Award in High School Chemistry Teaching. This paper is an adaptation of his address at the First National Student Affiliate Research Symposium in Aoril 1975. durine - the 169th meeting- in Philadelohia 552 / Journal of Chemical Education
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well as an instructor. I am going to discuss with you four major challenges confronting school districts in the United States. After this, I would like to share with you some of my own chemical experiences teaching high school chemistry. Interaction with Colleagues and Students 1) The first challenge is to find ways to allow the high school chemistry teacher to interact with teachers and young students to strengthen elementary school science offerings. A recent survev that I conducted in local school districts emphasizes the L e d for additional assistance in science a t the elementarv level. Elementarv teachers are rewired to provide competent instruction iifrom ten t o fifteen different subject fields, an obviously impossible task. Thus science is one of the neglected subjects because there are few science specialists in the elementary schools. Professor Joseph Novak, Chaiman of the Science Education Department a t Cornell University, recognized this fact early in the last decade and put together auto-tutorial learning materials from various areas in the hiological sciences for use in the primary grades. He was quite successful, and his efforts were accepted enthusiastically by elementary school teachers. Programs of this type should he developed for all districts. Another type of assistance could be made available if high school staff members were provided to teach model classes a t the elementary schools. Not only students hut also teacher observers could take advantage of such opportunities. Recently I had the pleasure of teaching a small section of a unit on gases to a third grade class. I must confess that their auestions were a sheer delieht. Aooarentlv they have not jet learned not to ask oh;ious qiestions, which all too often do not have simple answers. We realize, of course, that the simpler more penetrating the question in science, often the more difficult the answer. I thoroughly enjoyed this elementary school experience, and I would recommend it to others. Aid in terms of hoth materials and personnel are urgently needed a t the elementary school level. Training in mathematics, English, and social studies occurs in grades K-12. Why can't we have training in science? The expertise of high school chemistry teachers should be made available to the elementary schools. If school districts in this country make their programs more flexible, these kinds of opportunities may be offered. Feedback From Preceding Programs 2) The second challenge that concerns me is to find ways in which a high school chemistry teacher may aid and gain valuable feedback from the junior high school science program. Many of the proposed ideas for increasing the effectiveness of the elementary school science program would also be appropriate for the junior high school; however, a snmewhat different emphasis is needed. Most junior high schools do have science teachers, hut there is little or no interaction between these teachers and the high school science teachers. Without communication and interaction, teachers within the same district are essentially unaware of what other teachers in their own field are doing. T o allevi-
ate this nroblem. I would recommend that a hieh school teacher de established as a liaison person to provide books, materials. and es~eciallvinstructional techniques for more effective performance at the junior high school. Furthermore. there should be op~ortunitiesfor both junior and senior high school teache&to visit one another's classrooms. These kinds of interaction are vital, for when any part of the education process occurs in a vacuum, when the four walls of a classroom become the perimeter of one's intellectual scope and vision, i t is time for school districts to require change. Chemistry Teacher as Career Resource Person 3) A third vital challenge is to develop ways in which the high school chemistry teacher can be used as a vocational counselor at
his own school plant. Chemistry is one of the few subjects taught in high school that may lead directly to specific vocations. Since counselors simply can't keep u p with the constantly chaoging vocational requirements, many fields continue to be unknown and unexplored by the typical high school student. The ever-expanding field of materials science, for example, still has many challenging . - career opportunities. Chemical engineering, nuclear chemistry, and petroleum and energy enzineerine also appear to have considerable career poten.. tiai when projected available positions are compared with the number of young adults planning to enter the field. Many fields, such as laboratory technician or instrumental analyst, require minimal preparation. These positions could he adequately handled by trained junior college students, but again many, many high school students are unaware of these possibilities. Unfortunately, students seem to think that entry into the field of science is limited to creative geniuses such as Max Planck, Alfred Werner, or Linus Pauling. A large support force is also needed, and the high school chemistry teacher can help students become aware of the wide variety of career possihilities. The chemistry teacher must function as a liaison between the chemical industry in his own area and the high school. He should be in a position to arrange for speakers, to plan field trips, and to acquaint students with career opportunities. Vocational education, while expanding, continues to be much too fragmentary. Not only local but also national efforts must be expanded, and to this end the services of the national and local ACS divisions would be of immeasurable value. As a direct contributor t o the career needs of our society, the chemistry teacher then must expand his role. I t is no longer adequate for him to limit his responsibilities to classroom instruction. Interdisciplinary Role of a Chemistry Teacher
4)-The fourth challenge that concerns me is to find ways in a normal school format to enable the high school chemistry teacher to act as a resource person in his own school. Students must learn t o understand and appreciate the interrelationship and interdependence of suhject disciplines. T o facilitate this understanding, I would propose a number of ways that the chemistry teacher might become a resource person in his own school. The social sciences, for example, include a number of courses in which scientific knowledge is a prerequisite to discussion of some aspects of the topic. In the anthropology course a t our high school, students were interested in learning about the various ways used to determine the actual age of cultural artifacts, as well as in the assumptions the chemist must make about the reliability of these processes. In the psychology course, problems occur which require an understanding of the manner in which a specific molecule interacts with some part of a hody cell, a concept in molecular biochemistry. As
the chemistry teacher functions as a guest lecturer or is made available for individual student conferences, his stature is increased in t%e eyes of students and their motivation for learnine is thus increased. Other departments or courses which would benefit from working cl&.ely with the chemistrv teacher include mathematics and, in the science department, biology. Since modern molecular biology involves understanding the chemical processes which occur within every cell of our hody, I can conceive of a core teaching situation with the chemistry and biology teacher working together. I have long wanted to work with a class utilizing the "blue version" molecular biology approach to understanding principles and processes in living organisms. I imagine it would he great fun and very intriguing. While the foregoing ideas cannot exist in the school systems that function traditionally, I have hope for the future. With added wisdom, with insight, and with imagination, school districts will vary schedules and use teacher time and talent more resourcefully. The ultimate goal of all education must be to provide better and more effective educational opportunities for students. Personal Reflections and Student-Involved Experiences 5) Now let me share with you the personal view of one high
school chemistry teacher that enables him to communicate his Lave for chemistry and the fascination it holds for him to his students. In spite of his potential use as a curriculm consultant and resource person, the chemistry teacher is first and foremost a teacher. He is also a perpetual student, constantly askina questions and exdorina everv source of additional knowledge. By sharing his own love for chemistry and the fascination it holds for him, he becomes a model for his students, for his primary goal in teaching is to capture the curiosity and imagination of these young people. Let me share some of my own experiences that illustrate my passion for chemistry and my love for the students with whom I work. First of all, my time for this subject is never limited to the regularly scheduled classes. Recently my students saw a film by Professor George Pimentel, University of California a t Berkeley, on an advanced discussion of the effect of quantum theory on how we perceive and think about the atomic systems. This film was shown in the morning before school started. As time permits, I take groups of interested students through California Institute of Technology since our high school is only a few miles away from this famous campus. I will long remember the pleasure I had in taking a group to chat informally with Professor Linus Pauling. No truly dedicated chemistry teacher could ever limit his pursuit of the fascinating subject of chemistry solely to the school day. Another way to communicate with students is through the exneriences offered in conductioa a modest research program. Some of the experiments we are currently working on in our high school laboratory include the following: One is the sulfamic acid-sodium nitrite reaction, a chemical system that is truly beautiful to work with. This can be used initially to calculate the gram-molecular volume for an ideal aas (1). In this reaction. it is nossihle to obtain nitrogen(lfi) oxide as well as elementai nitrogen. After running this reaction, I wondered how important the side reaction really was in changing our experimental results. I wrote to Robert C. Brasted, Professor of Chemistry a t the University of Minnesota, and I learned that he had puhlished a series of papers on this reaction in the forties and mid-fifties (2, 3). As he shared his work with us, we learned that the amount of nitrogen dioxide seen is, under optimal conditions, but a fraction of the total gas produced. Thus the production of this small amount of nitrogen dioxide creates a minor error in the measurement of the volume of the gas because of its solubility in water. Professor Brasted suggested that using large crystals of sulfamic acid in the
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vial prevents a large amount of acid from reacting with sodium nitrite to form dinitroeen trioxide or nitric oxide and nitrogen dioxide. He furthe; suggested that the dinitrogen trioxide forms in the same stoichiometric ratio as the elemental nitrogen and actually does not change the volume measurement except for the small solubility error. In order to minimize this reaction, then, one needs a slight excess of sulfamic acid reacting with the sodium nitrite. Professor Brasted states, "As you will agree, there is lots of fun chemistry in this experiment, one in which the student learns a fact of life: control. When we do not watch carefully for side reactions, we lose control of a reaction. We are in trouble" (4). Incidentally, this experiment, as Professor Brasted pointed out to us, is much safer than the old potassium chlorate molal volume experiment with manganese(1V) oxide. since students mixing anvthine black. like carbon. will generate an explosion. 6rofissor brasted further sug: eested that we ~ r e c i ~ i t athe t e sulfate ion formed with bariGm chloride and t h i s have an effective way to analyze for the nitrite ion which is difficult to determine by usual analytical procedures. Another modification is to use a short length of glass tubing filled with glass wool and weight the reacting flask before and after the experiment to determine the required stoichiometric calculations. Thus a simple experiment has many valuable ramifications and allows students to learn a lot of chemistrv. Another interesting chemical system is the cis- and trans-dichlorobis(ethvlenediammine~cobaltII1 chloride. This classic experiment is beautifully described in a laboratory manual edited by Professor Jerry Bell, Simmons College in Boston. (5). I t is possible t o study the aquation of this complex a t a given temperature with different amounts of starting material and then to further study the rate of aquation a t different temperatures in water. Analysis can he made for the chloride, both total and ionic. I t is also possible to analyze the ethylenediammine in a standard Kjeldahl procedure. This gives a slightly different experimental twist than analyzing a coordination compound for ammonia. The striking color changes which occur during aquation and further preparative conversion to the cisform are extremely interesting to a student who has never worked with coordination compounds. I must confess that I will he thinking of intriguing pedagogical uses of this compound in one way or another as long as I remain in chemical education. Often in routine demonstrations interesting questions are presented. When preparing hydrogen in an electrolysis experiment, a student of mine wondered whether it was safe to simply use the vapor pressure of water to determine the pressure of the dry hydrogen gas. He was concerned about the fact that we were usine a 3 m solution of sulfuric acid and felt that a Raoult's L ~ Wcorrection factor should he taken into account. At these concentrations of sulfuric acid, we discovered, the required correction amounts to approximately a torr or less in pressure. Much can be learned in applying a simple idea in an unfamiliar situation. In other words, we were in electrochemistry, hut the student remembered that we had discussed colligative properties earlier in the year. Questions and calculations such as these make teaching and learning fun and demonstrate the value of checking on the initial assumptions underlying any experimental procedure. Students are constantly posing ideas. Recently a student suggested the use of a copper wire for the salt hridge instead of a 1 M solution of ammonium nitrate in the preparation of simple Galvanic cells. We tried it and i t works. We even tried a salt bridge filled with distilled water. That also works. We want our students activelv eneaeed in exoeriments, continually questioning and suggesting alternatives. I am constantly amazed a t the changes and modifications students offer. Their ideas, their slggestionb, and their 554 / Journal of ChemicalEducation
questions help make chemistry the exciting subject that it is. Still another experiment is in the chemistry of the transition metals, an area that I find extremely fascinating. Professor George B. Kauffman, California State University a t Fresno, has spent many years studying the chemistry of Alfred Werner, founder of the coordination theory of valencg (6). Professor Kauffman suagested that mv students and-1 try to resolve tris[(tetrammGe-r-dihydroxo-cobalt(1II)lcobalt(III) sulfate 4-hvdrate usine ammonium(+)-ahromocamphor-T-sulfonate as a reso6ing agent. w e a r e currently involved in this resolution experiment. Ranked among the world's greatest chemists, Werner first did this experiment to silence his critics. Before carrying out this classic resolution, he had used organic ligands in all previous resolutions; therefore i t was natural for his skeptics to criticize him on the grounds that all of his ligands contained carbon. T o end the controversy, Werner prepared this completely inorganic coordination compound and then proceeded to resolve it into its D- and L- forms 17). .. The student is sure to obtain great inspiration from doing such a monumental experiment. Fortunately there are several such experiments in Professor Kauffman's "Classics in Coordination Chemistry." My classes have had access t o university professors not only through correspondence and scientific literature but also as direct instructors and demonstrators. Two narticular situations show how effectively university personnel may he used. One of my students became interested in the separation of amino acids using high voltage electrophoresis. Since it is impossible to have appropriate apparatus for this technique in a high school chemistry lah, I called a colleague of mine a t Cal-Tech who set aside a Saturday to conduct a session on the theory of the newer separation techniques, not only electrophoresis. He then spent the remainder of the day working with a small group of mine in actually carrying out a separation using the equipment available a t Cal-Tech. At the end of the day, students received samples on their results and were extremely delighted with the experience. On another occasion a former student of mine, now doing post-doctoral research a t Cal-Tech, prepared a session on nuclear magnetic resonance spectroscopy. An informal session on the theory of nmr preceded a hands-on session, during which the students used the instrument to identify the unknowns. I am sure that all of this material was not intelligible to my students, but the opportunity to meet a former student who has continued in the field of chemistrv and the thrill of individually operating the instrument wili, I am sure, act as a motivating device in their future. Everv experience, every opportunit; should he provided for students to understand and appreciate the total panorama of chemistry which hopefully has been presented as both a science and an art. These have been the reflections of one chemistry teacher. You, the members of the American Chemical Society, are paying trihute to the many, many dedicated high school chemistry teachers across this nation who work hour after hour, day after day, week after week, and year after year to improve the education in chemistry of our nation's youth. We thank you. Literature Cited i l l Cunroy, Lawrence E.. Tobias, R. Stewart, and Brasted, Robert C., "General Chemistry Laborstory Operations."Znd ed.. The Macmillan Co., New York, 1911, p. 63. (21 Brasfed, Robert C., J. CHEM. EDUC.. 23.320 ( 1 9 4 ) . (3) Brasted,Robert C.,Ana!. Chem., 7.980 119511. (41 Brasted, Robert C.. private communication. (51 Bell, Jerry A,. Editor. "Chemical Principles In Practice." Addison-Wesley, Reading, Mssr., 1967.p. 181 (61 Ksuffman, George 5 . . "Alfred Werner: Founder of Coordination Chemistry." Springer-Vorle, New York, 1966. (71 Kauffman. George B., "Ciassicr In Coordination Chemistry." Dover Publieatians. Inc.. New York. 1968.p. 177.
