It's a liberal trait to constantly say "All we need to do is a and b, and then presto chango x will happen".
It's conservative to accept the reality of human limitations and human nature and to work with in that frame work in a non-ideological manner.
The fact of the matter is the human brain is a chemical- mechanical instrument just as is the thigh muscle. The computing functioning ability of some people's brains are just not physically capable of processing past a certain amount of information.
IQ is the term of measurement of this computing ability in brains just as hertz is the unit of measurement for CPU performance.
Someone with an 85 IQ can no more do Advanced Algebra, than can an Intel 386 run Windows 7. Having a staff of Nobel Prize in Physics winners as teachers wouldn't change that.
Now if we can get down to the reality that John Marshall High is about as likely to graduate a future MIT theoretical mathematician as New Trier High School is going to graduate a 100 meter Olympic Gold Medalist, then maybe we can come up with reasonable policies both economically (protect manufacturing so low IQ people can have a job, stop undercutting them with immigration) and educationally (return of trade schools).
Something has changed, and it is not a sudden appearance of low IQ's. But it does coincide with the sudden appearance of teachers unions.
I believe that it is the lack of discipline and and a lack of performance required of both students and teachers that gives us only 38% of white four-grade boys being proficient at grade level.
If that level of performance sounds good to you fine.
I believe it is unacceptable.
Shifting subjects slightly, this is a core concept at the heart of Thomas Sowell's book The Vision of the Anointed. He calls this "The Tragic Vision". The other side of that coin is "The Vision of the Anointed", which can be quickly summarized as Really Smart People from Washington, New York, and Harvard telling The Benighted how to live their (our) lives. Because They Know Better.
If you haven't read this book, I strongly recommend adding it to your reading stack. I'm about 80% through at the moment.