Prism - January 2002
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by Henry Petroski

Policing the classroom

It used to be understood that whoever used a classroom's blackboard was responsible for erasing it at the end of the period so that the next lecturer did not have to begin with the chore. The rule was seldom written down or even conveyed orally to new faculty members or teaching assistants. It was expected that everyone subscribed to the common courtesy that you left things pretty much as you found them. In the cafeteria chairs were to be pushed back to the table and in the classroom blackboards were to be erased as thoroughly as possible, save for the boxed announcements in the corner, which, also by unstated good sense, were kept to a reasonable size.

Similar unwritten rules applied to the students and to their sphere of responsibility, the desks at which they sat. In those wooden pencil days, they were to leave no pencil sharpenings on the floor, nor any crumpled paper under the desk. Even the chewing gum wrapper, which was supposed to be saved to wrap up the used gum, was dropped in the wastebasket (though the gum sometimes found its way beneath the desk). Other than the inevitable mud tracked in on a rainy day and the accumulation of chalk dust on the board and in the tray beneath it, the classroom in the late afternoon looked about as it did in the early morning.

A teacher of the old school entering a classroom today can get a rude awakening. The blackboard may not have been erased for several periods, each panel of it bearing the sketchy notes from a different lecture. Especially after lunch, the wastebaskets are likely to be overflowing with trash, bulked up by fast food containers brought from the student union and emptied during class. The floor is likely to be full of half-read student newspapers and half-empty soft drink containers and spring water bottles, if they have not been spilled on the floor. When I invite distinguished guest lecturers to meet with my class, I must ask my teaching assistant to police the area beforehand.

Smoking has been banned from today's classrooms, but eating has not. Indeed, institutions of higher learning might be said to have encouraged the practice of students bringing their lunch and snacks to class by the proliferation of fast-food counters and vending machines located around campus. (The lack of a vending machine in an academic building can generate as many complaints as the lack of parking spaces beside it.) No food and no drink policies in libraries and classrooms are routinely ignored by the students and not enforced by faculty and staff.

Have students come to view attending a classroom lecture as something akin to watching a movie or a television show? How can they concentrate on the more subtle aspects of engineering science while eating a taco, reaching down now and then to grab the drink sitting on the floor, and sometimes knocking it over in the process? Can those students who ate in the last class concentrate on the lecture when they have to worry about kicking over their neighbor's drink? Can teachers who have not yet eaten concentrate on the blackboard with the smell of a hamburger or chicken sandwich wafting past their noses?

If confronted with the matter, some students fail to see anything wrong with what they are doing. After all, they ate in front of the television set throughout childhood and snacked in classrooms and libraries throughout high school. Even in college, student organizations and academic departments have lured them to empty classrooms for lunch- and dinner-time recruiting meetings with the promise of pizza and soft drinks. (On some days, a campus drive can seem to have more pizza delivery cars than FedEx trucks parked before the buildings).

Students will argue that their busy class schedules do not leave them time to eat: There is not enough time between classes and, besides, their professors keep lecturing well beyond the allotted time. These complaints may be true, for I have found it to be the case that fewer and fewer students are in their seats at the beginning of class. The students tend to trickle in two, five, ten, twenty minutes late, often carrying some hot food and a cold drink. Was it waiting in a so-called fast food line that contributed at least some to their tardiness?

Could it all have started with faculty members neglecting to erase the board? Did the litter of previous lectures give students the impression that they too can leave a residue of their presence behind? Perhaps returning good manners and clean floors to the classroom might begin with faculty members policing the space up front at the end of each lecture. Even though the chalk dust will be thick by noon, an erased board will at least suggest a tabula rasa. But will a blackboard example soon be moot, as more and more professors now carry a laptop computer and a projection system into the classroom? Perhaps walking into a room with a perfectly clean blackboard behind a stark white screen will give students even more of a hint about how they should leave the floor.


Henry Petroski is the A.S. Vesic Professor of Civil Engineering and a professor of history at Duke University. His latest book is "The Book on the Bookshelf".
He can be reached at





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