The new math was set theory and group theory, in the form of “clock arithmetic”. At least this is what I got in 9th grade as groundwork for algebra. It was real math, at least, and did teach the basics of Abstract Algebra.
Since then there has been “fuzzy math” and the “new new math.”
Numbers are abstract.
It’s as if the CC math is an attempt to help certain students that had difficulty adding Apples to apples.
Something in our education system was lost a long time ago if this is what they think they need to do to teach math.
I got it in second grade. That was probably too young for a student to get anything other than beginning arithmetic.