Socializing Education Lowers Its Quality

http://lastfreevoice.wordpress.com/2008/11/10/the-cult-of-the-omnimalevolent-state

Ah, by "tragedy of the commons" here you mean the lack of per-family
ability to shop for more efficient schools and to capture the marginal
savings caused by exerting such consumer pressure. Yes, those are
essential features of competition, and are somewhat analogous how
efforts to care for a commons are not properly rewarded. However, a
true commons has to be inherently non-excludable, rather than being
something that by government fiat is currently shared. Alas, forced
sharing can create commons-like tragedies for any kind of good.