BOL!
A few years ago one of our younger relatives became the village idiot in math.
His parents got him in Kuman, and in a few months his teacher was getting math tests from two to three grades ahead of him to keep him challenged.
We found out that he had two years of Californiacator new math and the last year was the precursor to the current math excuse.
Years later he is still at the top of his class in math skills.
When he was having problems, his sister, two grades of ahead of him would come to school in the morning and find her home room/ his math teacher in tears, because she didn’t know how to present the math lessons for that day. Our younger relative would show her teacher how to present the so called new math.
That teacher’s reason for trying to teach math, she was the least in tenure.
My wife’s a great believer in Saxon because it simply lists the lessons from k-12, whatever that might be....a thousand steps...(I don’t know). What it boils down to is they build on one another.