Thoughts on the nature of teaching science in the 21st Century

As I suggested in my earlier piece, “Final Exam in Contracts”, I see very little emphasis on the application of knowledge in today’s classroom, especially in the science classrooms. The impact of the “No Child Left Behind” legislation was an emphasis on testing and the easiest testing is simple recall of facts type testing. True learning will not come when an individual is able to recall certain bits of information but when they are able to process that information and develop new information from the information that they are presented with in the classroom.

Many years ago, I proposed that the purpose of teaching was to prepare individuals who could proceed on their own after completion of that particular class; in effect, removing the need for teachers. Right now, if you were to ask a classroom teacher at any specific grade what their purpose in teaching was, they would say that it was to prepare the students for the next grade level; i.e., from the 1^st grade to the 2^nd, from the 2^nd to the 3^rd, and so forth up to high school.

High school teachers will tell you that their purpose is to prepare their students to enter college, even if college is not the goal of the students. My research into the nature of the college introductory chemistry course showed that most high school chemistry teachers saw their purpose in teaching high school chemistry was to prepare their students for the introductory college course. Even though that research was twenty years ago (and probably should be redone), anecdotal evidence suggests that it is still true today. Students come into college courses expecting to see the same information presented in the same way that it was presented in high school and are not prepared to move intellectually beyond that same level.

Preparation for the next level is critical but should it be just to give the information that they will need. What would happen if a particular class at a particular level was the last time a student was taking that course? Would they have the skills necessary to move beyond the level they just completed?

I realize that, at certain levels, especially the early elementary grades, this is merely a philosophical exercise but at the higher grade levels, are the students prepared for the world beyond the classroom when they leave the classroom? I contend that our educational system is designed otherwise, for success only in the classroom and continued life in the classroom.

(The following comments are directed towards chemistry at the high school and introductory college level but are applicable to other topics at the same level.)

When I began working on my doctoral dissertation, I was intrigued by how the nature of the chemistry textbook had changed over the years. An examination of one of the chemistry textbooks my father used in the late 30’s and early 40’s shows a mixture of chemistry knowledge and chemistry application. But an examination of today’s chemistry textbooks, while showing much in the way of knowledge and theory shows very little in the way of application.

Now, perhaps we should define these terms: knowledge, theory, and application. Knowledge will be the facts obtained through experience and experimentation; theory will be the explanation of those facts and application will be the usage of those facts in practical ways.

Now, it is understandable that the knowledge of chemistry has changed over the years and the theory that has explained those facts has changed as well. This is understandable. After all, when my father took chemistry, there were only about 90 elements on the periodic table and many periodic tables showed the transition metals as subsets of the representative elements (the A and B classification of older periodic tables). A footnote on the periodic table indicates that two new elements had been discovered and were tentatively named alabamine (Ab) and virginium (Vi). However, it was also noted that the discoveries had not been verified. In another textbook of that period, element 41 (what we identify today as niobium) is identified as columbium and element 43 (technetium) is Masurium.

Any explanation of the chemical behavior of the elements was limited to an understanding of the atom at that time. While isotopes were known to chemists and physicists of that time, the explanation was “unique”. Consider the following:

1. Atoms are composed of two sub-atomic particles called protons and electrons.
2. Protons have a positive charge; electrons have a negative charge.
3. There are two types of electrons: those in the nucleus of the atom (otherwise known as nuclear electrons) and those that orbit the nucleus (otherwise known as planetary electrons).
4. The sum of the charges of the protons and nuclear electrons determines the atomic number.
5. Protons have a mass of approximately 1.673 x 10^-27 kilograms which we call 1 atomic mass unit. Electrons have virtually no mass (9.109 x 10^-31 kilograms). This means that the mass of an atom is determined by the number of protons that an atom has.
6. For example, ¹²₆C has an atomic mass of 12 (determined by experimentation) and an atomic number of 6 (again, determined by experimentation). The 12 protons give this atom of carbon its mass; the electrons are divided into 6 nuclear electrons and 6 planetary electrons. The charge difference between the protons and the nuclear electrons give the atomic number of 6.
7. Carbon also has an isotope with a mass of 13 (¹³C). It must have 13 protons and 7 nuclear electrons to go with its 6 planetary electrons.

The definition described above is the explanation of atomic structure based on the knowledge of the time. It’s just that the textbook was written in 1934. (First Principles of Chemistry, Brownlee, Fuller, Hancock, Sohon, and Whitney, Allyn and Bacon, 1934; Chemistry For Today, McPherson and Henderson, Ginn and Company, 1934; these were the books that my father used in high school)

Even though the neutron was discovered in 1932, as the publication date for the textbook indicates, the incorporation of this new information took several years before it was included in subsequent textbooks.

The application of the knowledge of chemistry focused on processes such as the commercial production of sulfuric acid or aluminum. For every page devoted to chemical knowledge and theory, there was a page devoted to the application of such knowledge.

In the 1950’s and 1960’s there was a perceptible shift in the makeup of the chemistry textbook. Information concerning commercial application of chemistry was reduced as theoretical information increased. This was a reflection of the shift in the emphasis in science education during that same time frame.

At the present time and as a result of the shifts in the college chemistry curriculum during the 1960’s, high school chemistry matches and essentially duplicates introductory college chemistry courses.

What is interesting is that it shouldn’t have turned out this way. In the early 1960’s, as Americans reevaluated the nature of science teaching in general, chemists were looking at chemical education. The prime conclusion of this study was that while there needed to be a strong emphasis on the theoretical nature of chemistry, it should not be done at the expense of the heart and soul of chemistry, descriptive chemistry. In addition, college chemistry curriculum changes of that era were predicated on the idea that high school chemistry would maintain something of the traditional approach.

The high school chemistry courses developed during the 1960’s, while shifting in emphasis from traditional descriptive chemistry to a more theoretical basis still maintained the emphasis on the use of experimentation to support and develop theories (a process that is often reversed in introductory chemistry courses today).

It is interesting to note that the two major chemical education projects developed in the 1960’s and which are the literary ancestors of the majority of today’s chemistry textbooks (CHEM Study and the Chemical Bond Approach) both approached the teaching of chemistry from an experimental and developmental viewpoint. The CHEM Study was developed to enable

“. . . the student to acquire a knowledge of chemistry, not merely some knowledge about it. Abandoned are authoritarian pedagogy for teaching, descriptive chemistry facts for content, memorization for study, and regurgitation for evaluation. Instead, the student is engaged continually in the patter of scientific activity – experimental collection of data, assessment and organization of facts, deduction of unifying principles, and application of these principles in developing expectation (making predictions).” (Pimentel, G. C. and Ridgway, D. W. “CHEM Study: Knowledge of Chemistry”, Science Activities, 8(3), 40 (1972))

Ramsey summarized the goals of the CHEM Study program as:

• to stimulate and prepare high school students whose purpose it is to continue the study of chemistry in college as a profession; and
• to further in those students who will not continue the study of chemistry after high school an understanding of science in current and future human activities. (Ramsey, G. A. A Review of the Research and Literature on the Chemical Educational Materials Study Project, Research Review Series – Science Paper 4, Ohio State University, p. 2 (ED 037592) (1970))

Similarly, the goals of the Chemical Bond Approach were:

• to devise a course for high school students that would be basic for future study in college and better relate the first year of college to that of high school chemistry;
• to develop critical thinking in students;
• to present chemistry in a logical course; and
• to present a course that would be on the intellectual level of average chemistry students as well as offering a challenge to the more advanced students. (Osborn, G. “Influence of the Chemical Bond Approach and the Chemical Educational Materials Study on the New York Regents Examination in High School Chemistry”, School Science and Mathematics, 69, p. 53 (1969))

In conjunction with these philosophies was a concurrent thought that high school chemistry would continue focusing on the application of chemical knowledge (which became known as descriptive chemistry) while college chemistry focused on the theoretical portion of chemistry. Unfortunately, despite the thought that there should be a strong emphasis on theoretical chemistry but that descriptive chemistry should also be continued to be emphasized. It was felt that this could only be accomplished if high school chemistry continued the traditional approach and let college chemistry focus on the theory. However, high school chemistry quickly took on the look and feel of college introductory chemistry courses (and continues to do so today).

But, in making the shift from a descriptive approach to a theoretical approach, certain things became apparent. First, many students could not distinguish between experimental evidence and theory. In what is a classical description of the problem, Derek Davenport noted that students thought that silver (I) chloride was a pale green gas.

While grading a beginning graduate inorganic examination some time ago I was startled to discover that the student believed silver chloride to be a pale green gas. Now we all have our off days…and I read on willing to forgive and forget, if not to allow partial credit. A little later the student launched into a long plausible explanation as to why silver chloride is a pale green gas. I was reminded of Dr. Johnson’s: “I can give you the explanation, M’am, but not the understanding of it.”…

That we should begin by setting up a skeleton of inorganic principles is undeniable. Without it the presentation of facts becomes inefficient and their accumulation a shapeless mass of protoplasm. Instability and stability, lability and inertness, oxidation and reduction, acidity and basicity, and their relationship to position in the periodic table are as much a part of modern inorganic chemistry as is ligand field theory….
….It takes effort — what in teaching doesn’t — but the effort must be made. For as Conrad urged: “Every sort of shouting is a transitory thing, after which the grim silence of facts remains.” (“The Grim Silence of Facts”, Derek A. Davenport, Journal of Chemical Education, 47, 1970, p.271 (from http://bouman.chem.georgetown.edu/general/davenport.html))

In light of Dr. Davenport’s comments and with the knowledge that introductory chemistry textbooks today have effectively removed descriptive chemistry, we have to ask ourselves what the future for introductory chemistry might be.

The removal of descriptive chemistry from the chemistry curriculum, for whatever reason, has effectively made the presentation of theory become the presentation of fact. This in return means that many instructors do not have any idea how science operates or what it is that chemists do.

I have presented what I considered a brief synopsis of how science operates in “The Processes of Science”.

And, with the emphasis in today’s classroom for testing, students are further removed from any understanding of what science is and what it does. This is clear when you examine the lack of understanding in a number of topics that impact our lives each day outside the classroom.

Among these topics are:

1. Energy – not only energy production in today’s society but energy sources (renewable and non-renewable) for tomorrow
2. Global warming – if there was every a topic that called for the public to have a knowledge of science and its role in society, it is global warming.
3. Environmental chemistry – how we view recycling and what can go into landfills and what cannot
4. The role of chemicals in our environment – I would include the issue of mercury and mercury compounds in the preservation of vaccines and what this may or may not do. I would also include the use of the word “organic” to mean pesticide and insecticide free produce (when all foods are organic in nature).
5. The debate for free thought in the classroom – if I was a biologist, I might have entitled this the creation/evolution debate but I am not a biologist. But to me, this issue has several impacts besides biology; it goes to the issue of free thought and what our responsibilities as scientists and educators should be. It also speaks to how we, individually, believe.

Additional Questions

There are several other questions that arise from this discussion (again, I have phrased these questions in terms of chemistry but they are probably applicable to other subjects as well):

1. Should the goals of high school chemistry be the same as those of introductory college chemistry courses? Or should there be a complimentary nature to these goals?
2. What course should a student take in college if they did not take a high school chemistry course or did poorly in their high school chemistry course?
3. When should descriptive chemistry be included in course materials? Should it be integrated with the normal course or an additional course to be taken either earlier or later?
4. Where does laboratory work fit into this process? Is laboratory work critical to the understanding of the course material or is merely needed to supplement course materials?