How in the blue blazes could some mystery department of ed 1500 miles away know what is best for Missouri students?
Because educational standards should be universal, and not depend on the wealth of your neighborhood.
Math, science, literacy, history, and other subjects are the same everywhere, and there is no reason why there have to be different standards for them. Just as there is no such thing as Texan math and Californian math, there is no such thing as Floridian biology or Oregonian chemistry.
By decentralizing education, you are tempting each district to adopts its own standards, which is exactly what has happened. Worse yet, the standards are proportional to their ability to fund their teaching, which vary depending on local taxes and therefore local income. No matter how stringent the standards, it is impossible for a district to live up to them when it has no funding to teach them. The end result is that mediocrity thrives, which is exactly the case in the United States, and it is why we are an embarassement to the world.
Not to mention the feds already exceed their constitutional authority on schools anyway.
The Constitution makes no proscriptions on education, and even if it did, can be amended. I'd have to wonder what you mean by exactly how it exceeds its authority currently.
No, if anything the feds need to get the hell out of schools.
Not like the quality of education has gotten better since the Department of Education has been established.
That is because it has little authority to do anything other than write carte blanche subsidized student loan checks. So naturally there would be little effect.