When chalkboards are used, chalk flies and gets in sinuses and lungs. Dry-erase boards present a problem if markers with volatile organic compounds (VOCs) are used with them. These and other classroom chemical hazards can have a cumulative effect on students, increasing allergies and lowering immunity, according to Jim Terhune, a health specialist with the Oregon Department of Education. His article can be found in the Washington State University's "Indoor Air Quality."
Kristen Dixon, a business director in a chalkboard and whiteboard company said that chalkboards, being made of slate, are much more expensive than dry-erase boards, in an interview with ABC News. She also pointed out the dry-erase markers are less expensive than they once were, and are now comparable to chalk prices.
Many teachers prefer chalkboards because they are usually larger. Other teachers like the idea that they can cut up large pieces of whiteboard material to make a small dry-erase board for each student.
Chalkboards are cleaned with chalk erasers, but can be washed occasionally to cut down on lingering traces of old lessons. Dry-erase boards can be cleaned with any soft cloth.
Both chalkboards and dry-erase boards can be used to relay and emphasize information that is important to students. Seeing the words written in large letters for everyone to see encourages students to pay attention, and doing problems on the board together promotes classroom participation. Jane Arledge, a math lecturer, says in an ABC News interview that dry-erase boards are better for making charts and graphs.