Common Core, now nearly two decades on its march to ...?
Recall that event in October 1957 that shocked many, even the American educational establishment (viz., a Russian satellite in Earth orbit - beep, beep, ... )?
That spawned "The New Math" and other "educational" programs. For example, if you finished high school in the early 1960s, you likely just missed all that "set theory" fun.
Moving to the 1980s - "The Nation is at Risk" sent up numerous red flags, the real results were several Presidents became the "Education President" - well, in name only it was realized.
So, now, Vos states, clear as sunlit skies, the obvious.
The last "quality" public education system in the United States ended in the early 1960s.
Just a surmise, public education in the United States today is ineffective and can not be fixed - think of the VA as a similar dyfunctional organization.
You do not get the time back. Words are not Actions; Actions are not Results. [Or, EXPECT what you INSPECT.]
Where are the next generation(s) of teachers coming from, if any?
Yep, I graduated in '62, but when finishing by bachelor's I found that I needed a math course to complete my degree (1966). Never, fond of algebra and scared of calculus, I asked for an entry level math course. I was put in "Algebraic Principles of New Math"--whatever the hell that was. We learned about sets in elementary school but didn't know it at the time. "You can't add apples and oranges unless you call them fruit." --Simple, easy to understand.
Well, just for fun they decided to make that complicated with base this and base that. Now, I had no objection to logic or reasoning, but when I found that you needed 21 steps to prove that 1 is greater than 0, I lost it.
I did manage to escape the course with a C.