Revamping High-School Science: Herding Cats

I am concerned about the discussion in Physics Today dealing with the order in which biology, chemistry, and physics should be taught in high schools ( September 2001, page 11; February 2002, page 12). Where in these discussions is geology considered?

I often begin my introductory geology classes with the statement that geology is the most difficult science. My arguments are based on the degree to which the understanding of one science is contingent on understanding the other, the degree to which the basic data of each field are knowable, and the degree to which each science is presently described mathematically. Chemistry relies on physics for understanding, biology on chemistry and physics, and geology on all three. The basic data of physics are largely knowable through experiments whose results are often explained mathematically. This is progressively less true with chemistry, biology, and geology. Consequently, an understanding of geology often starts with existing theories from the other sciences that explain qualitatively the information gleaned from the incomplete 4.6-billion-year record of all the physical, chemical, and biological phenomena that have occurred.

To some scientists and educators, this qualitative nature means geology is an "easy science." However, recognizing that geology will be quantitatively understood only after the other three establishes it as the most difficult of the four. The only argument for geology's ease is the extent to which it can be taught to students with little mathematical ability by using the basic principles of the other three sciences.

I believe that a high-school science course is only the most basic introduction to the field, that principles are more important than mathematical descriptions at that level, and that the principles of the sciences depend on each other in the order I've presented here. On the strength of that belief, I submit that the order of courses in high school should be physics, chemistry, biology, and geology.

All students should take physics, but should do so even sooner than in the ninth grade, the level that Leon Lederman recommends. Students, though, must know basic algebra before taking physics, because even if one emphasizes concepts, the understanding is deeper when the instructor also introduces quantitative treatments. Thus, any academic revolution needs to change the K-8 traditional math courses and bring in algebra well before the 8th grade. By age 11, the average child is capable of abstract thought and reasoning. In some European countries, students learn algebra in the 5th grade and begin physics in the 6th grade.

We believe that K-12 schools should return to the classical education system in which schools require that every child learn the same core curriculum. Establishing such a common knowledge base is essential; it is how a culture is preserved from one generation to the next.

Numerous experiments and innovations in education during the 20th century were unsuccessful, which implies that basic improvements, not just more gimmicks, are needed. More money and more assessment are certainly important, but educators need to take a stronger stand on specific curricular approaches.

Challenge all children. Whereas the present system tends to focus on the lowest achievers, a more classical system challenges everyone to learn more than they are "comfortable with." As part of their constructive social upbringing, the highest achievers would learn to help those who are initially low achievers. Educators should recognize and appreciate that humans are fundamentally challengers--they enjoy attempting difficult things, especially if the social climate is supportive.

Match learning activity to age. Without being told to do so, young children memorize voluminous data and facts from their environment; it is better that children learn those facts from teachers and parents than from their peers. Memorizing basic essentials like multiplication tables and vocabulary, and practicing reading and writing skills, should be the main activities in early years. At age 11, children can learn the abstractions of algebra; at age 12, they can start learning physics; and at age 13, chemistry. From 7th through 12th grade, every child should take both math and science at every grade level.

Use spiral learning. The spiral learning approach promotes both interest and understanding because, during each cycle, the same topic areas are repeated in greater depth. For example, an introductory cycle of mechanics, electricity and magnetism, and modern physics in middle school would be followed in high school by another complete cycle of greater sophistication.

Emphasize core knowledge. US schools largely ignore science through the 12th grade, so students are less science-literate than their counterparts in most other industrial nations. For US students to compete in this increasingly technological world, they must receive considerably more instruction in basic skills, including physics. All students should take the same fundamental courses with few electives. This approach would reduce the need for academic counselors, who would then be free to teach, thus helping to relieve the teacher shortage and ensuring that class sizes would be smaller.

After reading Leon Lederman's comments and the responses by Michael Bretz, Ian Thomas, and Douglas Giancoli with Lederman's reply, I am compelled to respond from my experience in the high-school physics classroom. Order of classes, though a thought-provoking aspect of science education, is not the most relevant issue. The most pressing issue is teaching science as science is practiced, regardless at what level or in what order.

In his response, Lederman refers to the "firm, conceptual, and process-rich sequence I am trying to describe." It is this conceptual thread that runs through what is referred to as inquiry-based science teaching and student learning. As a public-school physics teacher, I am responsible to my students to get them excited about learning physics. This goal will not likely be achieved if we do not give our students time to explore and truly discover those phenomena that get us to work or school, allow us to enjoy music and art, or understand what (aside from pain) is involved when an outside linebacker makes a quarterback a part of the turf.

Two methods that allow for conceptual development are the learning cycle¹ and the conceptual change model.² In these inquiry-based methods, students are required to explore, discover, and, in many cases, change their ingrained perceptions of the universe.

Another aspect of teaching science, addressed by Giancoli, is the idea of cross-curricular teaching. True, we should not expect the biology teacher to teach the fluid dynamics of the circulatory system, or the chemistry teacher to teach the concept of cross sections when introducing nuclear chemistry. Yet teachers need to team-teach occasionally to show students how truly connected all of the disciplines are. At my former high school, I team-taught a lesson with the social studies department chair during his unit on World War II. He taught the political aspects of the Manhattan Project and I took on the military and scientific aspects. The students were quite surprised that two teachers of differing disciplines would take the time to teach in this manner, and their attention was not difficult to maintain.

As with any change, there will be plenty of system and procedural inertia to overcome. Tackling this hurdle will require systemic change in teacher preparation and professional development, which I thought Roger Tobin, Ramon Lopez, and Steven Bittenson addressed nicely ( Physics Today, January 2002, page 10.)

Lederman is certainly accurate in saying that the Third International Math and Science Study results should be a red flag indicating a serious lack in our public-school science classrooms, but let's not take tests to the extreme that our body politic is suggesting. Let's use them to generate dialogue about how to repair the problem, not to affix blame.

If inquiry-based teaching and learning are to truly take hold in this nation's science curriculum, time is a critical factor. Inquiry comes at a cost in both dollars and time. In Richard Rhodes's book, The Making of the Atomic Bomb (Simon & Schuster, 1986, p. 108), Theodore von Kármán, seen by most as the architect of the space age, said of his science education, "At no time did we memorize rules from a book. We sought to develop them ourselves." Rhodes added, "What better basic training for a scientist?" If it worked for von Kármán, it will work for our children. As Plutarch said, "The mind is not merely a vessel to be filled, but rather a fire to be kindled."

The proposal by Leon Lederman to teach physics in the 9th grade seems like a call for reviving, no doubt with modifications, a course that existed in New York State for decades. That course included topics in chemistry, and certification to teach it required at least two years of physics and two of chemistry.

Because the 9th-grade population is so diverse, the course has to be adaptable for different groups. The February 2002 issue of The Journal of Research in Science Teaching gives many examples of the problems faced by science teachers in urban settings.

Sadly, in the public schools of Norwalk, Connecticut, the 9th-grade science course is Earth science. That may be because so few of the teachers have had more than one year of physics.

Leon Lederman argues for putting physics experiences--whose understanding is enhanced by sketching speed-versus-time graphs, applying Galileo's "isolate the system" idea, and drawing free-body diagrams--in the 9th grade with an aim toward molecular biology in the 11th grade. I suggest an ecology-based biology course in the 9th grade.

An ecology course, while including graphical analysis and the concept of the isolated system, would stress developing an understanding of and appreciation for interconnected and interdependent systems. Students might then have some rational basis for deciding that "individuals in community" is often a more fruitful conceptual tool than those offered by either the worldview of extreme individualism or that of extreme collectivism. Furthermore, physics teachers might be encouraged to read and study George Gaylord Simpson's "Biology and the Nature of Science," in which he said,

I suggest that both the characterization of science as a whole and the unification of the various sciences can be most meaningfully sought, not through principles that apply to all phenomena but through phenomena to which all principles apply. . . . [Those] phenomena are . . . the phenomena of life.

Biology, then is the science that stands at the center of all [natural] science. . . . And it is here, in the field where all the principles of all the [natural] sciences are embodied, that science can truly become unified.¹

Lederman replies: Herding cats must be absolutely trivial compared to accomplishing anything in educational reform! Nevertheless, we cannot surrender. Education, even the subset we call science education, is an enormously complex system and, as I have often stated, the resistance to change is impressive. That is why the science education curriculum in K-12 is so poor and so antiquated.

About 10 years ago, I decided to spend a significant fraction of my time to try to create and "sell" a coherent three-year science curriculum. Colleagues and I (collectively, the ARISE group, American Renaissance in Science Education) have thought through the steps we must take to achieve a physics-chemistry-biology (P-C-B) sequence in at least a majority of US high schools. We are making progress; with more than 300 high schools doing it right, we have only 24 392 to go.

Three years of science in a sensible order, threaded with three years of math, would be a major advance. Of course it would only be a first step in reform of pre-K to 16 schooling. But practical politics mandates that science education reformers move one sharply focused step at a time. Each step must be capable of amassing a consensus among teachers, parents, administrators, and the 134 other constituencies that make up our educational system. A next step, following the compelling arguments of Gary Kinsland, would mandate four years of science and add geology or Earth and space science. And of course my colleagues and I strongly favor elective science courses like advanced placement and more. We must then examine and restructure the K-8 science and mathematics sequence along the lines argued by Lev Berger and Donald Rehfuss. Here I only insist that the design be for all children and within a flexible set of consensus standards; there should be a variety of local options for branch topics and for implementing teaching methods. We want to stress connections between the science disciplines and between the sciences and the humanities and social sciences, as Paul Rutherford articulated so well.

Martin Stewart has reminded us that teaching physics to 9th graders may well exacerbate the problem of teaching to students with a wide variety of preparations. But the few hundred schools now experienced in the P-C-B sequence seem to manage, and as we begin to create a seamless K-8 math and science curriculum, the problems will diminish.

The only difficulty I have is with Vinson Bronson, who, in my view, misses the point. I do not advocate teaching conceptual physics in 9th grade, because of speed-versus-time graphs and drawing free-body diagrams. These are important examples of how science works--and they illustrate some of the advantages of 9th-grade physics over conventional 9th-grade biology. However, in 9th grade, students should learn about atoms, their structure, and their behavior in company. Atoms make molecules--that is the basic theme for all of chemistry and, increasingly, for modern biology. It is this hierarchy that recommends 9th-grade physics before chemistry and biology. My comment on Bronson's last quotation: Biology is not at the center of the sciences, but at the pinnacle. Physicists, chemists, and mathematicians rejoice in the growing comprehension of life, and we are proud to support the pyramid, on top of which sits triumphant biology.

It is difficult for me to understand, however, how the "phenomena of life" are relevant to cosmology, astrophysics, particle physics, the solar system, the quantum principles that support condensed matter physics, or even the earlier phases of geological history. But George Gaylord Simpson was a great biologist. Why do I have an uneasy feeling that I am the one who is missing the point?