I do agree that we need national standards in this matter. The Common Core is needed as it gives a set of common goals which must be present to give a consistency to the whole education system. The education policies and standards must be set by people who are actually eligible in that field. The Common Core will set standards and only then quality will be given importance over quantity. But teachers also must be given the freedom to teach adhering to the standards. I will share the links of two articles in this regard,