Chalkboards enable teachers
and students to present written material to the whole class.
Teachers use chalkboards to present written material to students in a classroom setting, much in the same way as they use whiteboards, smart boards and projectors. Chalkboards were once a revolutionary technology in classrooms, and many teachers still use them as primary or supplementary teaching tools.
History
James Pillans, geography instructor and headmaster of Edinburgh, Scotland's Old High School, invented the chalkboard by placing two pieces of slate together on a wall. Chalkboards first appeared in American schools in 1801 and became indispensable tools in most American classrooms by the mid-1800s.
Composition
Chalkboards were originally made of black slate and were known as blackboards. By the 1960s, manufactures switched to pouring liquid porcelain over steel boards and painting them with a gritty dark paint. Because this paint was often dark green, brown or blue, instead of black, the term "chalkboard" gained popularity.
Benefits
Chalkboards enable teachers to present written information to a room full of students at once, a task that was nearly impossible before the early 1800s. For young children learning to write, writing with chalk on a chalkboard is easier on their hands than using the more modern whiteboards and smart boards.
Considerations
Some people fear that the dust particles from chalkboards can cause or exacerbate respiratory problems or damage classroom computers. Most classrooms reduce this risk by using nontoxic low-dust and dust-free chalk. If the chalk box says "AP Nontoxic" or "Conforms to ASTM D4236," toxicologists have deemed it safe for classroom use.
Fun Facts
Albert Einstein did much of his important work using chalkboards. Though chalk was once made of sedimentary rock, it is now typically made from limestone (calcium carbonate) or gypsum (calcium sulfate). (
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