Compulsory Schooling is Compulsory Schooling

I stumbled upon this while link-hopping earlier.  In a post entitled “The Intellectual Underpinnings of the Charter School Movement,” the blogger writes:

KIPP’s new bumper sticker slogan: Work Hard. Be Nice.

Translation: SHUT UP (work hard) AND DO WHAT YOU ARE TOLD (be nice).

My question is: How is this any different than the intellectual underpinnings of public schooling?  I realize the quote above isn’t saying it is, but I’ve seen plenty of leftish types go on about Charter schools as if they’re self-evidently worse than public schools (usually it’s that they’re less accountable), and I don’t get it.  It reminds me of the hand-wringing over “private” defense contractors.  They’re both funded by taxes and they’re both ultimately accountable to the government, not parents (PTA show meetings notwithstanding) and definitely not the students (you’re joking, right?), and the model for both is basically authoritarian.  Charter schools are just public schools by another name.