Back when I went to elementary school, America was just getting over the disaster of "New Math". So I learned ordinary math, using times tables, and drills. And at some point, I became smart enough to figure out on my own why the standard algorithms were correct and effective.
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It's certainly not the abstract woo that was New Math.
As someone who was actually taught "new math" in early grade school and who has a degree in pure math from a well respected Univ, I heartily disagree with your assessment of "new math".
Introducing material based on fundamental concepts is far better than the alternative of teaching the rote detail and then trying to introduce concepts later. So yes I learned discrete sets, unions & intersections of sets, Venn diagrams associativity, commutativity, number bases, modulo operation and boolean logic by 3rd grade and this foundation was indeed very helpful in university study of group theory, topology and concepts of abstract algebra and homology theory. Yes basic arithmetic was taught in grade school along side and used to motivate as example.
To me your preference of teaching rote arithmetic first, is akin to forcing piano students to learn to bang out a Chopin Sonata on their own, and only then teaching them about octaves, chords, major/minor keys and proper fingering and hand positioning. They need to
unlearn their biases and bad habits before they can advance, and
unlearning is IMO much harder than learning. Further, rote repetition avoids engaging the student's abilities at abstract reasoning.
A better analogy might be the way that most ppl including physicists have trouble overcoming their early intro to Newtonian mechanics, classical E&M and particle theory vs relativistic & quantum Mech. We are all crippled by biases that introduced early and are hard to unlearn.
I've no idea if "common core" per se is good/bad or indifferent, and frankly no one can know until some careful and controlled tests have been performed. It has aspects that sound very good, particularly the ability to measure results in a consistent way. I'm a little concerned that it may prevent progress in education by classifying exactly which 'unit's must be taught at each grade level. It seems over-restrictive in dictating a time-line rather than just unit goals.