>>11395006The problem is that it's massively inefficient for certain problems. Children should really taught to understand mathematics, not just to memorise different tools for performing calculations. Common core is just as bad in this respect as other teaching regimes.
As you said, you have been able to derive common core techniques yourself without being taught them, and this is because you understand arithmetic. You could come up with different ways of attacking the problems common core cannot solve efficiently precisely because you weren't taught common core; instead you received a more fundamental and significant mathematics education.
