Where Did Chalkboards Come From?

Hear that? It's the sound of thousands of schoolteachers resuming their swishy-click marking up of our nation's chalkboards. The ubiquitous learning aids have gone through some evolutions since the days of one-room schoolhouses. Back then, students carried their own wedge of slate, reusable and cheaper than paper, and took notes on their laps. Larger chalkboards—sometimes just pieces of wood painted with black, liquid slate—hit the wall in the early 19th century, when they were introduced to America by a Scottish geography teacher at West Point Academy. A greenish hue is more popular today because it is considered less harsh on the eyes. Concerns over dust allergies are also spurring the use of "whiteboards," porcelain-based boards written on with squeaky, colored markers. So much for the eraser-cleaning detention.

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