so much for Common Core https://www.usnews.com/news/education-news/articles/2019-10-30/across-the-board-scores-drop-in-math-and-reading-for-us-students
In the district I used to work, teachers were baffled and frustrated by the abrupt way in which the curriculum change was handled. All of a sudden, every student in middle and high school had been taught the "wrong" thing and in the "wrong" way their entire lives. It showed me just how damaging a "teaching to the test" mentality could be. As soon as the test changed, their entire educative history became irrelevant because the students had never developed the verbal and reasoning skills that they needed to handle information presented to them in new ways. Sure, they learned how to read, but they didn't learn how to critically assess what they read and sure they learned to solve algebra equations, but they didn't learn how to use that knowledge to make decisions based on their findings. Of course, there are many different directions to point the finger of accusation, which I won't do here, I'm just pointing out the fact that at least a whole generation of students in my old district were flat-out screwed out of a proper education.
Eh, saw this coming. My wife and I have always taken our son in for standardized testing in between school years to evaluate where he is versus where he should be. At the end of 5th grade he tested proficient to 7th grade. At the end of sixth grade he tested proficient to 5th grade. Reason for this was likely curriculum change but there was also the complication of private school tuition and a headmaster's wife teaching sixth grade math. Result: we took him out and homeschooled him through to end of 8th grade. End of story, he's now in 11th grade having completed algebra, pre-calc and calculus 1 at the extension school in Cambridge and absolutely crushing the current high school curriculum. Moral, it's not just the system or the teachers. Parents need to take an active role in teaching their kids, providing them opportunities or at a minimum being involved with their teachers in a way that doesn't corrupt the outcome or damage relationships. Any curriculum that is intended to teach everyone, inevitably leaves out a lot of people or doesn't teach them to their capabilities.