“The teacher wrote equations on the chalkboard for the class to solve.”

“A schoolhouse on the same compound had a chalkboard with instructions on how to make roadside bombs, he said.”

“Lisa, the teacher, exclaims over each answer, scrawling it on a chalkboard at the front of the room.”

“The next morning, chalkboards and desks reappear right where teachers left them, but for a few brief in-between hours, anything can happen.”

“Light and chalkboards are perhaps the two most important things for physicists.”

“The school employs zoned lighting, to improve visibility and readability of chalkboards, white boards or projector screens.”