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Discovery-Based Discourse

Byron Waksman

In the current wave of teaching reform in the nation's schools, scientists are in position to play a crucial role. Simply put, we are models of what everyone agrees pupils should say and do. We investigate, we think critically, we imagine, we use intuition, we are playful, and we think on our feet and with our hands. "Hands-on," "discovery-based" activity is what we do for a living.

The connection between doing science and teaching science to youngsters ought, therefore, to be an easy one to make. Clearly scientists can contribute directly to the design of new teaching models—and have. There has been much development of science-teaching programs over the past 20 years, with activity ranging from systemic curriculum reform to enrichment programs that train teachers in the use of new hands-on methods.

Some of us, however, are still watching from a distance. I have been fortunate to have been pulled from the sidelines—in my mid-70s, retired from active research in microbiology—directly into the classroom. My interaction with 12-year-olds since 1996 has provided an outlet for my energies, a use for my accumulated knowledge and experience and immense personal satisfaction. I hope that telling the story of this experience will encourage other senior scientists to venture into the classroom as well, to be "live" models engaged in conscious interaction with the scientists of the future.

A few years ago New York University Medical Center forged an agreement with the Salk School of Science, a New York City public school, that allowed NYU faculty members to teach science to Salk pupils in a medical setting. The program is patterned after the work of Michael Shayer, who during the 1980s introduced a "discovery-based" teaching method in a number of British middle schools, basing his approach on Piaget's stages of psychological development and Herman Epstein's studies of brain growth. He called it CASE (Cognitive Acceleration through Science Education). The use of nontraditional science teaching not only enhanced the measured cognitive and reasoning skills of students in tests over 3–4 subsequent years but also spilled over into nonscientific disciplines such as English.

Epstein, at Brandeis in the late 1960s, had introduced into college and then high school teaching a method in which science students would study individual research papers dealing with a particular line of work, focusing class discussion in each case on the activities of the scientist who wrote the paper. "We continually ask students to put themselves in the place of the experimenter and figure out what to do next and how to do it," Epstein said. "This is the orientation of problem-seers and problem-solvers."

My involvement with the program has been typical. Each school year a graduate assistant and I schedule seven monthly, 75-minute encounters with the 60 children making up the seventh grade at Salk, split into two multiethnic, multicultural groups of 30. The seventh-grade teacher helps us understand the characteristics of 12-year-old children, makes suggestions and critiques successive exercises as they develop. Our encounters consist of a 15-minute illustrated talk by the senior scientist, followed by assignments of small-group tasks. The tasks are completed in 10 minutes, with support from the teacher, junior scientist and senior scientist, and one or two pupils representing each small group then make a presentation to the class. The senior scientist and science teacher wind up by summarizing the important points brought out in the student presentation.

How does this work in real life? Some snippets from our very first session in 1996 will, I hope, allow me to share the flavor of the experience. Subsequent sessions used experimental autoimmune encephalomyelitis and multiple sclerosis as models for exploring topics in immunology research. We endeavored during these dicussions to bring out elements of process in the scientific material: data and interpretation, laboratory methods, bioethical concerns and the interaction of science and society. For instance, we discussed how model diseases in animals might shed light on human diseases; we compared cellular and molecular techniques of investigation; we talked about the human and social implications of disease; and we looked at the Food and Drug Administration's role in protecting against bad science and quackery. (Add-ons to this exercise in 1997 and 1998 have been descriptions of the new epidemic disease monkeypox in Central Africa and the use of smallpox as a microbiological weapon by the British during the American Revolution.)

Reaping Rewards

Our experiment is in the middle of its third year. Objective evaluation of its effectiveness will be difficult but important. At this point the experiment has the earmarks of success. Active thinking, discussion and presentation by the pupils themselves dominate class time. They are essentially given the opportunity to function as scientists. The format challenges the students at a conceptual level and provides an unparalleled opportunity to develop their presentation skills. (Famous scientists, one has a chance to point out, are also good speakers who look their listeners in the eye and don't wave the pointer about.) Robert J. Walker, my first graduate assistant, is now teaching science at the Dr. Sun Yat Sen School, a junior high school in New York's Chinatown. And the students at the Salk school, which in just three years has become enormously popular as a choice of parents, were singled out in recent weeks for having, as a group, scored 35.9 percent higher on citywide reading and writing tests than students of similar backgrounds from other schools.

But I describe the experience not to advocate the method, simply to show how scientists might contribute directly and effectively to education of the next generation of scientists. Senior scientists no longer "at the bench" constitute a largely untapped resource whose energies can and should be channeled into active school-teaching when the opportunity presents itself. Retirement, by freeing us of the traditional demands of academic life, provides the time needed for developing effective interactive teaching modules and the needed illustrative material, as well as for the actual teaching. Graduate students (and occasionally postdoctoral fellows) must accommodate their teaching activities to the demands of their coursework, reading and research. Their activity as teaching assistants can be regarded as equivalent to coursework or, more aptly, an apprenticeship designed to prepare them for their teaching careers. (At NYU plans are nearly complete for the creation this September of a combined track leading to a Ph.D. in biomolecular sciences and an M.A. in science teaching.)

The setting for our small experiment was favorable: The Salk School of Science is a magnet school with a supportive administration and faculty and students likely to become scientists. We had the use of classrooms at the NYU Medical Center to remove the pupils from the distractions of their customary environment and invest each monthly exercise with a sense of its uniqueness and its potential significance for the practice of medicine and conquest of disease. Not all such exercises will have so much going for them. But for an able and energetic senior scientist who likes children and is capable of expressing the firmness, loving acceptance and warmth needed for dealing with them, a carefully designed partnership with a local school offers an effective way of passing along a valuable lifetime of knowledge.

A Scientist Visits the Salk School of Science

BHW: Good morning. I am Byron Waksman. I am a professor at New York University and an immunologist. We will talk a lot this year about virus infections and immunity and later about diseases related to the immune system, which I have worked on all my life. This is my assistant. He will introduce himself.

RJW: Good morning. I am Robert Walker. I grew up in upstate New York, near Syracuse. I am a graduate student at NYU, a molecular biologist, studying how proteins are made. After I get a Ph.D., I plan to teach.

BHW: Today we will first talk briefly. Then we plan to hand out some pictures and questions to go with them. You will be divided into groups of three or four, and each group will have 10 minutes to study one of the pictures and try to come up with the answers to the corresponding questions. Finally, there are presentations: One person from each group will speak to the class as a whole for a few minutes, describing the picture (which we will put on the screen while he or she is talking) and answering the questions. Mr. Berkman [the science teacher], Robert Walker and I are available to help you, while you are studying whichever picture you are assigned, and we also may comment during the presentations. Our intention is to be helpful, not to criticize.

Now, to get started: How many of you know what chickenpox is? [Show of hands by essentially all those present.]

How many have actually had chickenpox? [Show of hands by some, usually more than half the class.]

Up until a few years ago, there was another widespread children's infection resembling chickenpox but more severe. It was called smallpox. How many of you have heard of it? Does anyone care to describe it? [Hands, answers, comments.]

Here is a picture of a young child with smallpox [Slide 1]. It used to kill as many as half of the children who became infected. Those who survived had bad scars, especially on their face [Slide 2]. Boys scarred in this way suffered great loss of self-esteem and often had problems all their life. Girls were often so disfigured they could not get married—200 years ago, they and those around them perceived this as a disaster.

An English gentleman, named Edward Jenner, with a house in the country, noticed that the girls on his farm were not pockmarked; they had that beautiful rosy English complexion you read about. He asked about this and learned that they got an infection on their hands from milking the cows, called cowpox; once they got over their cowpox, they would never get smallpox. Here is what cowpox looks like. [Slide 3, Jenner's drawing, below.]

Click to Enlarge Image

We know that smallpox and cowpox are caused by very closely related viruses. Jenner was seeing an immune reaction, but also he understood that the immune system couldn't tell the two viruses apart. As you know, getting chickenpox doesn't make you immune to measles—those are two viruses that are really distinct. The immune system is very specific: It easily recognizes them as two different things. Anyhow, Jenner tried putting some material from a cowpox sore into the skin of a healthy child and later showed that that child could not get smallpox (or, as we would say: the child was immune to smallpox). How do you suppose he showed that? [Answers, some correct.]

That's right: He actually tried infecting that child with live smallpox. Could we do a human experiment like that today? [no] Good! We certainly couldn't. We have committees of doctors and ministers and ordinary citizens to decide what human experiments are permitted.

[Handout 1, flyer from Jenner Museum.] This handout shows a picture of Jenner putting the cowpox into the little boy, also Jenner's house and garden and a map of the area where he lived in Gloucestershire, England. They made a permanent museum of the house in his honor, because he had made a great discovery.

Now, how many of you speak Spanish? [Some hands.] Does anyone know the Spanish word for "cow?" [Vaca?] That's right. "Vaca" is really the original Latin word—remember Spanish comes from Latin. Medical people used to use Latin and Greek names for all their medical terms, because they didn't want ordinary people to understand what they were saying. So Jenner called his new procedure vaccination after the Latin word for "cow."

It is now 200 years since Jenner discovered vaccination as a way of immunizing against smallpox. People gradually began to use it to protect their children. Yet, less than 50 years ago, there were still lots of cases of smallpox around the world. Look at this! [Slide #4, map of world showing smallpox cases in 1950–55.] There were so many cases—remember, many of the people who got infected died—even though we knew how to vaccinate people and protect them.

Well, finally the World Health Organization, which is based in Geneva, Switzerland, put on a big push in the 1970s to get rid of smallpox by isolating infected individuals and vaccinating everybody who had any contact with them until, at last: [Slide #5, magazine cover announcing "smallpox is dead."] The disease really was conquered as a result of this worldwide effort.

[Question from second row: I read that they are keeping stocks of live virus in two places. Is that true?] Yes, one in the U.S. and one in Russia. Should we be doing this? Is it dangerous? [Lively, brief discussion; question unresolved.]

Let's move on now. Mr. Berkman is distributing the handouts with pictures and questions that you are going to study.

Click to Enlarge Image

[The science teacher distributes handouts containing nine pictures with accompanying questions to all students. He assigns groups of 3–4 students the task of studying individual pictures and coming up with answers to the corresponding group of questions.]

Students studied the assigned pictures for 10 minutes while the senior scientist continued to list unfamiliar terms. Students gave talks individually or in pairs, representing the small groups. They used a pointer and were asked to describe the assigned picture, projected on the screen. The students had thought of the minimal satisfactory answer virtually every time—and often came up with additional answers that were not anticipated.

Sample question sets and minimal satisfactory answers:

Representative clinical chart of a typical case of smallpox.

Describe course of fever. Up and down.

Are there separate phases? Yes, at least two.

How do these phases relate to skin lesions? (definitions: macule = spot; papule = bump; vesicle = blister; pustule = pimple; crust = scab) High early, then falling, high again during pustular phase, gradually returning to normal.

The decline of epidemic smallpox, 1971–79

Where was the largest reservoir of disease? India.

Figure 1. Small portion of the WordNet lexical graphClick to Enlarge Image

Why did it disappear so fast? Human disease, no animal reservoir, good vaccine. (These suggestions came from the senior scientist. The students could not answer the question.)

Where were the last cases? Africa, India, U.K. (Laboratory infection!)

What were the keys to success in eradicating smallpox? Will and determination.


The author was assisted in the preparation of this essay by Robert J. Walker. He gratefully acknowledges the support provided by Anthony Alvarado, Veva Zimmerman and New York State STEP, and the cooperation and help of Alexis Penzell, Ann Geiger and Robert Berkman of the Salk School of Science. He thanks William J. Newman, Jerome Gross, Jack Rosenbluth, Arnold Stern and Jasmine Gruia-Gray for critical reading and much helpful discussion.



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