Chalkboard is a smooth, dark board usually made of slate, glass, or wood. Crayon or chalk is used to write or draw on the board. The chalkboard is probably the world’s most widely used visual aid to education. Instructors use chalkboards to help emphasize classroom lessons. Chalkboards were once black, but many are now green.
The chalkboard grew out of the hornbook of the 1400’s and 1500’s. The chalkboard was in fairly common use in Europe by the 1600’s but was not widely used in the United States until the early 1800’s.
See also Eraser.
