I haven't done a lot of research, but from the few public school teachers I know personally, I glean that a lot of state and federal public school "regulation" is not of the explicit legal type, but rather takes the form of pressure from conditional subsidies.

> "propaganda in schools" is hard to effect from a centralized location.

What do you think of the new "common core" standards?

> Public education is administered at the county level

Admitting that as being partially true, and/or not wanting to quibble over where it isn't, it's worth pointing out that will be a fallacy should Common Core become widely adopted.

It's also worth noting that public schools have been used for indoctrination for a very long time now. You'd have been hard-pressed to find a college grad in the early thirties who believed that the government had the Constitutional authority to implement Obamacare, while you'd be hard-pressed to find one now that believed it didn't.

While much of that is attributable to the actual practice of legislation, and the past 80 years of precedent, education, particularly history, is continually being "updated" to reflect modern sentiment, and applies that to the distant past.