What I say, and what they hear

I teach biology at a small college in central Maine. All of my students are non-majors, and the modest curiosity they bring to the class is easily exceeded by their abject fear of science. As a result I often wonder - as does every teacher from time to time - if I am getting through. When, after describing a biological process or concept, I ask, "Does everyone understand?" I am often greeted with empty stares. In such instances, there truly is no way of knowing (until they are confronted with a test) whether my students are grasping the material or not.

Or is there?

From time to time I find a notebook that a student has left behind after class is dismissed. I approach the thing with cautious abandon, hoping the student's name is on the cover so that I don't have to open the notebook to look for some ID When I do see a name in plain view, I heave a sigh of relief. But when I don't, I gird myself for a descent into the inner sanctum of their notes, never knowing what I will find.

The surprises fall into several categories, the foremost of which is the "unsolicited editorial comment." For example, after a recent lecture on food chains and the social benefits of eschewing meat in favor of fruits and vegetables, I found a wayward notebook with no name on it. Inside, though, was a set of neatly printed notes - and accurate, to boot - that contained the following addendum: "Vegetarians are wrong!"

A more startling category is the caricature, generally flattering. This was the case with a notebook belonging to a student who was evidently bored with my lecture, for she had sketched a picture of me, which included the gloss, "Nice sweater."

But the category of notebook that disconcerts me is the one that records comments I know I never made. For better or worse, these are the types of notes that best tell me whether or not I am getting the information across.

For example, in my lecture on the history of cell biology, I refer to several scientists who laid the earliest groundwork in this area of study. One of these was Anton van Leeuwenhoek, a 17th-century Dutchman who was the first to observe microscopic life with his simple microscopes. I always emphasize that Leeuwenhoek did not invent the microscope; he only used it to study his specimens.

"Repeat after me," I tell my students, "Leeuwenhoek did not invent the microscope."

Like a Greek chorus, they comply. And yet, with this mantra still echoing in their ears, I later discovered a notebook, opened it, and found scrawled there, "Leeuwenhoek invented the microscope." I could not, in this case, resist the impulse to add the necessary correction: "He did not."

That was the only time I ever annotated a student's notebook without his or her knowledge. What I didn't foresee was the chain of events it would set off after I returned the notebook to its owner. A couple of days later the young man approached me, bearing a modest, recently published volume on the life of Gregor Mendel, the 19th-century Moravian monk who first formulated the modern views of heredity.

"I want to show you something," the student said as he opened the book and pushed it at me. There, in black and white, were the words, "Leeuwenhoek invented the microscope." Then the student looked up at me, as if to say, "So what do you think of that, Mr. College Professor?"

"Well," I said, unmoved by what he considered immutable proof of his rectitude, "that author is mistaken."

"But it's in a book!" exclaimed the student.

Our confrontation ended in a draw, with neither of us willing to relent. Of course, I was confident of my knowledge of the facts, but that didn't stop this student from stirring up the class with his carved-in-stone evidence that I was wrong about a landmark event in the history of biology.

There ensued a melee of cross-examination of several of the tenets of cell biology I had presented. I soon felt like a politician whose constituency was slipping away.

I had only one recourse. I ran to the nearest computer and found the website of the author of that book. I gently but directly informed her that Leeuwenhoek had not invented the microscope, and that it was a common misconception that he had.

The next day the author sent me a gracious reply, acknowledging the mistake and pledging to rectify it in any subsequent printings of her book.

I printed out her e-mail and read it to my class, like a proclamation. They took my word that the document was authentic, and peace was restored among my students, including the one who had raised the fuss.

And then one day, after my class was dismissed, I saw it - a lone notebook, lying in state in a storage compartment under a desk. I went over and examined the cover at arm's length. No name. I laid my hand upon it and paused. Should I or shouldn't I?

The day was clear, sunny, and warm, with robins singing in the trees. I turned heel and went out to that beautiful weather, convinced that sometimes it is best to let sleeping notebooks lie.