Why don't we speak Esperanto?
You know Esperanto. It's a constructed language created in the late 19th century by a young man who was very interested in languages and who thought he might come up with a neutral language that transcended all the biases and baggage of previous languages. Ludwik Lazarus Zamenhof became an opthamologist, so he wasn't technically a language expert, but that shouldn't matter, right?
If we come up with a good solution to an issue in human society, can't we just get everybody to do that?
Well, no. That's not how human stuff works.
For one thing, Esperanto isn't really neutral-- it leans almost exclusively on the linguistic underpinnings of European languages while ignoring Asian forms. It's neutral only if you assume that the default position for humans is to be a white guy from Europe.
But more importantly, that's just not how language works. It is a living breathing growing thing that resists all attempts to lock it in place and force it to follow the forms prescribed by authorities.
That's why people love Latin. It's a dead language that never changes because nobody really uses it. Latin and Esperanto are like a really nice set of paints that you lock up in a closet and never use because that would mess them up.
But language has to get out and live and change and grow, all through being used by live human beings. Languages literally have lives of their own-- Latin did not disappear because all the Romans died, but because it slowly morphed into new languages (Italian, Spanish, French, Portuguese). Old English is technically English, but nearly incomprehensible to English ears centuries later.
Yes, it's seductive to people who don't really know much about language to imagine that we could design a language that was cleaner, more efficient, less messy, more orderly, and then we would just get everybody to use it in exactly the same way, and the world would be better. But that seductive idea is only seductive if you don't understand humans or language.
You see where I'm going. It's seductive to think that we could come up with a neat, efficient, one-size-fits-all education system that would be orderly and clean, and we just get everyone to use it exactly the same way. It's seductive to think that if you don't know understand education or human beings.
You come up with these systems and wait for the world to catch on to your awesome plan, or you leverage money and power to try to force the world to catch on to your awesome plan. But in the end, you're only embraced by a small community of like-minded people and rejected by people who insist on acting, well, human. Perhaps if they had written the Common Core in Esperanto...