By Harry Keller
Editor, Science Education
All teachers must learn certain things. For example, they learn about learning theory, classroom discipline, and how to write lesson plans. In addition, they learn the material and ideas of their chosen subject area. As I read articles about science education and communicate with many science teachers, I become more convinced that our teachers colleges are not providing the necessary learning to our future science teachers.
What is this necessary learning and why is it important?
To answer this question, you must first understand what science is. Science is not a bunch of “facts,” e.g., Mercury is closest to the Sun; prophase is the first phase of mitosis; force is proportional to the rate of change of momentum; igneous rocks are formed from molten rock. Science is an approach to finding out these things, a way of thinking, of solving problems. It uses the work of previous scientists and new data to be sure. So those “facts” are part of the learning but hardly the most important part.
So-called science facts are always subject to revision, but the means by which they were extracted from nature with great difficulty remains the same. We must teach some science content in order to have material upon which to apply the developing thinking skills of our students.
Science courses inflict lots of vocabulary on students too. Some words seem familiar but are used by scientists in a very specific manner. “Work,” for example, does not take place when you’re holding a heavy weight above your head – if you’re talking about science. Work is a specific and quantitative term in science. Other words seem entirely unfamiliar and even bizarre. In physical science, “entropy” is a made-up word for a measure of disorder in things.
Science education must provide the content of science including vocabulary, an understanding of the nature of science, and development of scientific thinking skills. Anything else is superfluous in primary and secondary education. In post-secondary education of science and medical majors, there’s more, but that part is not the subject of this discussion.
Without an understanding of the nature of science, students will not be able to interpret what’s going on around them every day. You read about global warming and conflicting claims regarding it. You read about protecting species from extinction and then about how 95% of all species in the history of the Earth have gone extinct naturally. You read about an energy crisis and then about how the price of gasoline is being manipulated by Wall Street traders and that the energy situation is just fine. All of this would be just entertainment were it not for the fact that so many countries are democracies, and the people are expected to vote, to make decisions, on these issues in elections.
John Dewey understood these issues when he wrote Democracy and Education nearly a century ago. Even Thomas Jefferson wrote about the necessity for an educated electorate (Notes on the State of Virginia, 1781-82, p. 274).
What is “the nature of science”? This question goes directly to the heart of what science education should do. It’s not enough just to present the results of science to students. That sort of approach is just the same as teaching history as nothing but names and dates. You can memorize it all and forget it after the final exam. The newly published draft of the Next Generation Science Standards makes note of this fact and focuses partly on learning about the nature of science.
Science takes a special world view. It assumes that the world, the natural world of physical objects, is understandable in terms that allow predictions. The essential quest of science takes on achieving that understanding. At the same time, all scientists understand that scientific knowledge can change. Moreover, they know what that change looks like. It’s rarely large and usually incremental. Einstein’s Special Theory of Relativity replaced part of Newtonian physics but from a practical point of view only made adjustments in it. On the one hand, it was a huge event in science. On the other, it was just a minor change that affected few ordinary calculations.
Scientific knowledge also tends to stand the test of time. Despite all of the brouhaha you read about evolution, it has stood up to a century and a half of strenuous efforts to overturn it. Darwin’s work, rather than being weakened, has been strengthened by immense additions to the fossil record, DNA work and more. Adjustments to portions of the theory have taken place, but the fundamental concept of evolution of species through survival of the fittest has remained firmly in place.
Many people fail to realize that science is not a means to answer every question that comes to their minds. We humans have a habit of asking unanswerable questions, and science does not answer such questions. Scientists understand which questions are inherently unanswerable and don’t even attempt to answer them. When they do undertake to answer questions, they do so with reproducible data that others can review and challenge.
Scientists know that all data are imprecise. No matter how many decimal places exist in a measurement, that number will never be infinite. Because they’re always working with imprecise data, scientists are careful to accumulate enough data to overcome the imprecisions and make conclusions that fall outside of reasonable doubt. So, when nearly every scientist agrees that the Earth is warming due mostly to “greenhouse gases” and that the increasing concentrations of those gases are heavily contributed to by man’s activities, you better listen. As the long-predicted consequences of this warming becomes visible, you should not ignore them. The cost-benefit ratios of doing something are not in the realm of science, although scientists can contribute information to that conversation.
Scientific thinking is another desirable outcome of learning science in school. This sort of thinking is akin to critical thinking and skeptical thinking. It’s about lots of facets of looking at claims and understanding how to process such information, which comes at us in large quantities daily from advertisements, pundits, and politicians. Because Carl Sagan did such a thorough job of explaining this area of scientific training in his book The Demon-Haunted World, it need not be discussed here in any depth. Simply put “baloney detection kit” into your search engine to find out all about it.
The point he makes is a simple one. If you have learned to think scientifically, you’re much less likely to be hoodwinked by charlatans, and they’re after you every minute of every day.
Today, you can be sure that science courses teach the content of science. It’s what the high-stakes tend to test for, and it’s the easiest stuff to present and review for teachers as well as the easiest to learn for students. It takes relatively little mental effort. No, it’s not the content that must be imparted to our future science teachers but the other two parts of learning science. Lectures, textbooks, and even demonstrations aren’t sufficient; they aren’t even a good start to learning these things.
Here’s a quote from Canon Wilson, who wrote this in 1867. It captures the essence of this subject in the context of a secondary science class.
The lecture may be very clear and good; and this will be an attractive and not difficult method of teaching, and will meet most of the requirements. It fails, however, in one. The boy is helped over all the difficulties; he is never brought face to face with nature and her problems; what cost the world centuries of thought is told him in a minute; his attention, understanding, and memory are all exercised; but the one power which the study of physical science ought preeminently to exercise, the power of bringing the mind into contact with facts, of seizing their relations, of eliminating the irrelevant by experiment and comparison, of groping after ideas and testing them by their adequacy in a word, of exercising all the active faculties which are required for an investigation in any matter these may lie dormant in the class while the most learned lecturer experiments with facility and with clearness.
It would be easy to add pages of quotes on this subject. It all comes down to learning science by doing science. That does not mean that students or would-be teachers must join the ranks of scientists. It merely means that they must be exploring the real world around them using the tools and ideas of science. Until they have collected their own imprecise data and attempted to interpret them without knowing beforehand how to do so, they haven’t begun to exercise those thought faculties that science classes should develop.
Teachers must themselves have this experience and much more of it if they’re to provide it to their students. They must read about the scientists of the past and how they explored numerous blind alleys before finding the right explanations. They must study the history and philosophy of science to be able to interact with student questions intelligently and to answer these questions with pointed and insightful questions of their own. In short, teachers must have lots of true lab experience along with lots of good reading on the history and philosophy of science.
What is a true lab experience? Why use the qualifier “true”?
Here’s why. Frederick W. Westaway wrote in 1929 the following. Westaway was a giant in the field of science education, and his books went through several editions.
Beware of the pseudo method of discovery. “Pour H2SO4 on granulated zinc, and you will discover that hydrogen is given off “!
Beware of verification methods. “Show that ferrous ammonium sulphate contains one-seventh of its own weight of iron.” This is simply asking for the evidence to be cooked.
When a boy works an experiment, keep him just enough in the dark as to the probable outcome of the experiment, just enough in the attitude of a discoverer, to leave him unprejudiced in his observations.
This discussion goes on for many additional paragraphs. This bit will suffice here. For the longer quote, click here.
This quote describes the two examples of false lab experiences. The first requires no discovery on the part of the student. The results are known beforehand, and the lab becomes quite dull. The second has a similar outcome. Frequently, these false lab experiences have another object in mind: learning to use lab equipment properly. That’s all well and good for those who will spend many more years in science labs, but it is hardly a suitable use of time for the many for whom this may be their last such experience. What does it matter to the business major about how to light a Bunsen burner or use a buret or operate an optical microscope? Add to the list of false lab experiences those whose sole purpose is to train students in the use of equipment, some of which may well be obsolete by the time the student graduates from college if not already obsolete.
Another area of false lab experiences arises from simulations. A complete discussion of the pros and cons of simulations and how they can be used would take far too much space here. Suffice it to say that simulations can be very valuable in helping students visualize difficult science concepts. So can good videos from the Discovery Channel or National Geographic. However, none of these constitute true lab experiences. Interestingly, a number of “hands-on” lab experiences are simulations.
If science teachers were to have more true lab experiences as part of their training, they would be providing more to their students, and students would have a much better science education. They would come out of school better prepared to face our increasingly complex world.
The issue of how to provide those lab experiences in situations where time, money, space, and safety issues intercede is fodder for another article. For now, accept that we must use every resource available to do so. One of these involves technology. We can use technology in many ways. However, we should always be aware that technology is supposed to make things “better, faster, cheaper” to take advantage of NASA’s motto. Simply throwing technology at a problem may result in none of those goals being realized and certainly not all three.
Our science teachers absolutely must learn science in order to teach it. Too many do not. We can fix that. We know how. The problems with doing so involve institutional inertia and politics. It’s just possible that the new era of online education and/or online educational resources may provide the disruption necessary to foster the required changes.
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