If you really want to get depressed go back an read Federalist Paper #11. This is the chapter from the Federalist Papers on the dangers of factionalism in a democratic government. In my day, most High School students were required to read this somewhere along the line. In it Madison acknowledges the dangers of faction in a pure democracy and explains all the safeguards contained in the Constitution to avoid these dangers. Thus, the reasoning behind our Democratic Republic. If you go back and read this you will see that every saftguard noted by Madison is now gone. (Seperation of power between States and Federal government, limited government, independent, non political judiciary, etc, etc.)
We studied it as well.
That's the main danger of having the federal government in control of public education. Teaching selective facts instead of actual knowledge leads to an ignorant populace.