Common core was rammed through to prod without proper a/b testing or canarying. All the criticisms of the "New Math" of the 1960s are just as applicable to it t

Common core was rammed through to prod without proper a/b testing or canarying. All the criticisms of the "New Math" of the 1960s are just as applicable to it today. See Morris Kline's «Why Johnny Can't Add» on archive.org.