There was this strange fad of repainting blackboards to green in the early 80s, because someone thought white text on a black background was causing eyesight problems. I don’t know if that actually turned out to be true.
this post was submitted on 08 Jan 2026
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It was actually just that the world was black and white before that.
exactly, they were always green, but since the world was black and white some of them went cheap and put up a black board instead of the proper green.
When the world switched to color the black ones often were repainted.
Blackboards were often real slate. Chalkboards (note the different name!) were wood painted green. I don't know why the name was different, but that is what I always saw.
I couldn't find any reliable source, but the most convincing idea I read was to reduce contrast and glare issues between the white chalk and its background. The green would reflect more light than the black, reducing the contrast and the glare. Also, the original blackboards were made of black slate, but then they became synthetic which made it easier to change the color.
I don't think it's true but it's real that it may give problems to some people (especially astigmatic people)
I can still smell the air post eraser clap. Probably cancerous now that I think about it.
It was Tuberculosis they warned of.
In California.
It is known
Ahh, the lovely sound and feel of dragging your fingernails across the blackboard, fun times, fun times
I’m cringing just reading this
There are no gangster blackboards. You don't know what that word means.