Albert Shanker was a teachers union president (American Fed of Teachers) with a head on his shoulders and an analytical mind. 

For instance, this:

“It is time to admit that public education operates like a planned
economy. It’s a bureaucratic system where everybody’s role is spelled
out in advance, and there are few incentives for innovation and
productivity. It’s not a surprise when a school system doesn’t improve.
It more resembles a Communist economy than our own market economy.”

He said that in Wall St. Journal in 1989.