Classroom blackboards are being replaced with dry-erase boards.
Any student who attended school before the 1990s remembers the look, feel, smell and sound of chalk on the classroom chalkboard. Teachers in 2010 are much more likely to be using dry-erase markers on specially made "whiteboards."
How Chalk Is Made
Either calcium sulfate (from gypsum) or calcium carbonate (from limestone) is mixed with water and pigment, extruded into sticks and then baked.
Dry-Erase Marker Components
Dry-erase markers are composed of plastic barrels, caps, filaments and ink, according to an article in the Washington Post.
Using Chalk
Chalk is a low-waste product that can be used until it is gone, with no disposable parts; its main disadvantage is that it creates a dust which can cause allergic reactions and aggravate asthma in susceptible individuals, and can interfere with electronic equipment.
Using Markers
Although they are cleaner and brighter, dry-erase markers have an impact on the environment because once their ink is used up, they must be thrown away and cannot be recycled. Some dry-erase markers create fumes which may trigger allergies.
Use of Chalk Declining
As of 2010, most schools have replaced their chalkboards with dry-erase boards. Chalkboards are still popular in food and restaurant establishments which have frequently changing menus. BillyBoards Manufacturing, Internet chalkboard and dry-erase board retailer, says that chalk lends a personal feel and allows for more artistic expression than dry-erase markers.
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