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第13章

BLACKBOARDS

Large black, green, or dark gray wall-mounted boards made of either slate or enamel-coated steel; used primarily in schools, for either edification or torture.

? ? ?

It's hard not to have complicated feelings about the big rectangles that loomed large in the front of classrooms for so long. Blackboards certainly had their share of pros-they gave us permission to write on the wall, acted like larger-than-life Etch A Sketches, and insured that teachers would have to spend some part of every class with their backs turned to the students. When your name got called to the board and you found yourself standing framed by that black expanse, you couldn't help but feel kind of important-unless you were being forced to write one sentence over and over again, à la Bart in the opening credits of The Simpsons. That was when you suddenly remembered the hand cramps that came on as soon as you gripped a piece of chalk, the sneeze-inducing dust, the inimitable screeches that the board would sometimes inadvertently produce while being written upon, and the fact that facing it meant that a room full of people was staring at your behind.

For more than a century, the blackboard was really the only way to easily disseminate written information to a group of people all at once. In the early nineteenth century, American schools began experimenting with using slate slabs in classrooms-the United States Military Academy at West Point in New York is thought to be one of the first schools to have used them. It was a blessing for teachers who no longer had to copy out problems by hand for each student. Few other tools have been used so effectively by everyone from kindergarteners to physicists to football players. In the mid-twentieth century, green became the new black, as steel boards coated with moss-colored porcelain enamel began to replace the traditional slate boards. No matter the color, they had the odd quality of being kind of pleasant to wash; there was a Zen aspect to wiping a soft chamois or a wet sponge over the dusty remnants of math problems, and the cleaning of the erasers usually meant banging them to make irresistible indoor clouds. And we wonder why so many of us ended up with asthma…

But today, we're no longer so dependent on the dusty behemoths we all knew and scrubbed. In a world filled with Dry Erase markers, PowerPoint presentations, high-speed printers, and interactive white-boards (computer-projector hybrids), teachers have many options for conveying ideas to a classroom, making the blackboard far less of a necessity.

So you can finally sit down, Bart.

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