Why is the blackboard still widely used in education instead of the whiteboard?

Seriously, we have been using blackboards in university classrooms before. Although the old problem of dust and chalk dust is really annoying, there is no way, because some classrooms have been replaced by traditional whiteboards, and there is no dust, but the writing frequency in schools is too high, and the problem that the traditional whiteboards cannot be cleaned is more prominent. It won't be long before they get dark. Logistics has become soft, and I really dare not change it again. Later, brother colleges saw a glass blackboard completely different from the traditional whiteboard. Fortunately, the label is still attached to the Dianao glass white board, and it is very efficient to try it out immediately after installation. Sure enough, the reaction is different, mainly because it will not be cleaned and blackened again. Very good!

Ok, show the effect of our classroom installation.