It all comes down to our ass backwards funding and control of our educational system
Those countries that do better than us all have national control over the educational system. Only the US puts the power with the local school board....with widely varying results
Have you seen the tests that were given to students in those one-room school houses from the 20's through the 50's? Students could read, they could write (you could even read their writing) and they knew their geography and what little science that was available to them. Those that were taught in those 'locally' controlled school houses were people like Thomas Edison and others who powered the industrial and scientific revolutions in this nation. It is the main reason why the United States grew from a backward frontier nation to the one that lead the way in science and technology.
Right now if you want your children to get a good education you seek out private schools, probably some type of Christian private school (Catholic schools are very good) and you send them there. There is absolutely NO WAY that I would send my children to a public school now.
We have seen conclusively that you don't "teach" kids by trying to make them conform to some national standards that makes them all achieve to the lowest common denominator. We also know that the answer is NOT throwing money at the problem.