That assumes the US Department of Education actually improves education. Please show how US education is better now with it, than it was some years ago before it.
I'm not sure how you measure that... jobs? Literacy? Individual quality of life? I think a lot of people believe the USDE is ancient... when really it's just Carter's '79 pet. AFAIK literacy in the USA has been a steady 99% 15 and over according to the CIA World Factbook.
So... I don't know... are there any good studies that aren't a partisan mess?