The Cheese

A Brief Essay on Method in Science Teaching

by Michael Rossman


(A Lesson to Study)

        As I settle in with the fourth-graders on the rug, amid the usual horseplay, someone says it: "Who cut the cheese?" Much nose-pinching, a convulsion of giggles.

        I realize I've got my lesson for the day, and tuck the fossils I had brought discreetly behind me to avoid distraction as I ask, "Why do we call it 'cut the cheese'?"

        "It's like Limburger," they tell me -- most know that name, though it turns out only two have actually tasted or smelled it.

        "So what do we call it besides 'cut the cheese'?"

        Someone says "pass wind," another volunteers "farting". More giggles, but only a few. By now they are used enough to frank discussion of frank terms for biological functions that the shock value is almost gone, and they refocus their attention quickly in anticipation as I continue the familiar routine of domesticating charged material.

         "Does anyone know the fancy name for farting, the formal name?" They have welcomed the idea of two vocabularies, and pronounce 'feces' and 'saliva' like veterans now -- though they don't quite grasp why one should be spared embarrassment in adult company by using the fancy words. Nor do I, as I've told them, explaining it as a standard and useful agreement, while continuing to use the coarse and the formal words interchangeably myself, as equally natural and proper.

        But nobody knows this term yet, so we relish the syllables freshly as we chant them together: "Flat-u-lence! Flatulence! FLATULENCE!!"

        "Can anyone think of a similar word?" No one can, so I pronounce it differently, with a long a.

        "It's like 'inflate'," comes the quick response.

        "Which means ...?"

        "Blow into?" one ventures.

        "Right. So 'flatulence' is a name for a blowing. Where does flatulence come from?"

         All hesitate, but not from ignorance. Finally: "Your anus?"

        "That's right, your anus, or 'ass-hole.' And just what is a fart?" They know it's a gas of some sort. I ask how it gets into one's body. Opinions are various. Someone suggests that you breathe the gas in. I ask him to sketch the lungs while another child fetches the plastic body model. But quick study shows no connection to the anus.

        "Do you swallow it?" another offers, supported by a glad second: "Yeah, a fart's like a burp in reverse!"

        The idea is plausible, so we take a few minutes to experiment with swallowing air, forcing gulps down our esophagi until stomachs bulge in preparation for a brief salvo of belches. But what we learn, beside a quick way to gross out family and friends, is that what goes down that way comes up again, at least if it's gas and wants to bubble up.

         The mystery remaining, we attack it from a different angle. "Let's go back to the cheese. How come it smells, what is the smell?" Cheese smells because it gives off gas, they decide; for we've traced the progress of onion-gas before from the room's far corner to our stinging eyes. "But different cheeses have different smells," I tease, to invite the clear conclusion: different gasses.

        "And why does cheese give off gas?" No-one has the answer at hand, though they have all the elements for it. So we go back a step further. What is cheese, where does it come from? Milk, of course; but how? Five voices are eager to supply the known answer: bacteria, they eat the milk and change it. And the gas, then? The bacteria must give it off. Why different gasses? Different bacteria!

         Emboldened by something making sense, we return to the original smell. What makes our gas? "Bacteria?" Could be; but what would they be eating? "Leftover food?" Is there enough? Clearly there is. Indeed the lower intestinal tract is a superb pasture, and we marvel together at the statistic I supply: that as much as one-third by weight of what we defecate is no longer unused food or waste, but the homely intestinal bacteria that thrive on these in the warm dark until, unanchored, the stream sweeps them on and out.

        "Are they parasites?" someone asks.

        "No, they just live with us," I say. "In fact we need them. Some make certain vitamins for us that our bodies can't make for themselves."

        But before I can preach symbiosis, a more concrete imagination asks, "Why don't they all get swept away by the tur... the feces?"

        "Why are there still fish in the river after each winter's floods?" I counter. The key ideas come quickly: some find shelter in the stream-bed, others swim back upstream, they have lots of babies.

         After the children digest the idea of being hosts so routinely and on such a grand scale ("Thousands?" No. "Millions, billions?" No, trillions,) I say: "So if we all have that many bacteria in our intestines all the time, how come we all aren't always farting like cannon?"

        They puzzle this for a while, until they finally deduce that the different foods we eat may produce different fodders for the bacteria, and hence different products from them -- including less gas or more on occasion, and perhaps even different kinds of gasses.

        I run them through a quick chorus of "beans, beans, the wonderful fruit/ the more you eat the more you toot" to celebrate this solution to the problem. Our discussion has ambled already into so many terrains that I have no impulse to make it more complex and correct by describing the role of yeasts in fermentation or the production of gas through simple chemical (non-microbial) processes in our guts. Instead, to reward them for a track well-followed -- and to reinvoke the mystery of charge, now rendered inseparable from the science -- I tell them that our intestinal bacteria do indeed vary and produce different gasses, and that some people's flatulence will burn.

        "How can you find out if yours will?" they ask eagerly; and watch carefully as I demonstrate in mime the process of taking a container into the bathtub to trap one's farts, and lighting the result in the kitchen, with appropriate precautions.

        Though smelly, the gas is near enough to what flows through the stove that one might equally use it for cooking. And science flowers in ribald technological imagination, as I tell them that the bacteria in cows' intestines produce methane in quantity from chewed grass and grain -- and they figure that if there were only some way to keep the cows hooked up, the dairy herds of our land could gas up every stove, and maybe the water heaters too.

(About Academic Manners)

         When I first submitted the brief narrative above to a noted educational journal, it was rejected immediately, as if by reflex. Concerned for their readers' sensibilities, the editors feared that printing it among the other nourishing articles might seem as inappropriate as discussing flatulence at the dinner-table. Some readers here may still agree. But more, I trust, will find it quite proper fare for the lessons it illustrates.

        Casual and anecdotal, the story seems at first to be merely an odd little lesson in alimentary science. But it is equally a compact essay on the methodology of elementary science-teaching, fleshed in vivid example. Chewing it over, three themes of method emerge to be separately savored. They are not only themes but issues, for in each the lesson runs against the grain of common practice in science education.

         Indeed, our common practice is our custom at the dinnertable of learning where we serve the children. It leads us often to reject certain themes -- of subject, of method -- by reflex, as being in bad taste. Yet I think it's not only proper but important for teachers to discuss in print whether and how we discuss in class such charged topics as farting -- how we relate to children's attitudes, how we use their interests and energies. And it's useful too to discuss the other themes below, to recognize them as issues in method rather than as raunchy quirks of style.

 (Three Themes)

        1. Explore the method of no method.

        First off, what is the method that this lesson illustrates? It is like Discovery Method in the way it relies on students' input, proceeding through their observations and hypotheses. But Discovery Method is taught as an orderly, pre-planned process, focussed narrowly on experiment with prepared materials to develop particular insights as steps in a linear curricular process. By comparison, the method here is disorderly and impure: the lesson arises spontaneously, "randomly," and flows into many branches; and the teacher leads as often as he follows.

        Perhaps then "Discovery" is only one ingredient of this method? Sure enough, add these impurities and the other ingredients listed below and we get a much richer Method -- the Hyper-Socratic Method -- or at least its illusion. For the lesson's true method is not to be bound by Method but to use whatever one can that makes sense, in ways that fit the situation and must differ from situation to situation, teacher to teacher. Yet how can this be a Method, if it can be learned but can't be taught or precisely defined?

        Perhaps it's no method at all, but simply a rich mess. Even so, many children learn more per hour from such messes, even in what shows up on the tests, than they do from much more methodical instruction.

        2. Exploit the charge.

        Nervous titters and jokes about flatulence and other body-processes tell us how charged these matters are for children. Silences, excitements, body language identify other charged subjects: disease, death, decay, slime, spiders, explosions, sexual parts. The notion that science is an objective and dispassionate activity inclines us to take the emotional charge of such subjects as a distraction. Some teachers avoid them, others are careful to give them no more attention than they "deserve" in an orderly curriculum. But there are two good reasons to pay them attention proportional to the emotional charge they carry.

        First, the charge is there for a reason. It usually marks conflicted emotions of interest and unease, and invites us not simply to "desensitize" students but to help them explore and resolve their feelings, for the sake of their relation both to the subject and to feelings in general. Science class isn't the place to do all that's needed or useful, but even with such complex subjects as death and sex one can make a good beginning. The deepest lesson, of course, is social. We teach students that it's proper to talk openly about charged subjects, to share feelings about them, to inquire into them -- or that it's not okay to do this.

         Second, the charge is useful. It can serve to focus energy and motivate inquiry, and to etch learning in the mind. Teachers exploring charged subjects often find that children are unusually attentive and motivated in participation, listen more patiently (despite increased wriggling) and remember more. Of course, charge can be mishandled to make a classroom a circus or a subject an unpleasant experience. But it's never dull, and a remarkably rich and deep curriculum in general science can be developed simply by exploring charged topics.

        3. Connect.

        Our customary ideas about what science is and how to teach it lead us to isolate it from other domains of learning and life, and to make lessons narrowly linear -- focussed strictly on the topic, proceeding economically from one bit of information or principle to the next in methodical sequence, engaging only the mind and only its logical powers.

        In contrast. this lesson involves many sorts of activity as the students and teacher use their senses (smell), chant, draw, hypothesize, experiment with their own bodies, deduce, sing, calculate, imagine, and mime. The lesson joins one topic to another and science to general life as its focus moves in turn through metaphor, exotic cuisine, etymology, the culture of verbal manners, a rude music, domestic husbandry, a biological inquiry, folklore, what happens in the bathtub, and applied technology for the energy crisis. Even its strictly-scientific part is non-linear, connecting many domains as it touches on commensalism and symbiosis, comparative vertebrate physiology, human anatomy, fermentation, combustion, gaseous diffusion, steady-stream microbial culture, and the relation of scale to numbers.

        Yet with all this, the lesson is not sprawling and random, but organically-organized and coherent, moving purposefully through clear phases to a satisfying resolution. In this sense its underlying structure is as linear as that of any ordinary narrow "curricular unit," even as it weaves disparate information, topics, and activities into richly non-linear webs of connection. That the lesson weaves so is not incidental, but essential. For it is a lesson not simply about "flatulence," but also about learning, science, and the world, each of which is more intricately connected and non-linear in its nature than we can describe.

(About Practice)

        Nothing in all this is unfamiliar to good teachers. Their lessons regularly involve such fluidities of focus, activity, and connection, such openness of method and attention to emotional contours -- all of which contribute vitally to the strength, depth, and coherence of their teaching, in science as in other subjects. Still we tend to think of such graces as if they were distractions, or at best adornments to the "real" action of science teaching, rather than as central to it.

        Were we really to give them as much attention as we do to the skeletons of fact and method we convey, our ways of teaching science might change considerably. For lessons of such organic order and complexity as this -- both spontaneous and planned, appropriate to every age -- arise at any point in the fields of science and life if one chooses to see and carry them through. And enough such lessons woven together over the years could teach more science more deeply and systematically than even our best-balanced curriculum plans attempt.


-- published in Phi Delta Kappan 64:9, May 1983

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