I bet that if we switched to vouchers then you'd see a lot of new private schools catering to a wider audience. It also might be reasonable to exclude private schools with religious instruction from the voucher program.
I'd like to be that optimistic, and maybe it'd happen, but the politics around here would make it unlikely.
Also, wrt the exclusion of religious schools, that'd be a non-starter in the southern states at least. It'd probably make more sense to mandate some minimum curricula or require that inspectors be able to attend the school unannounced if the school is receiving public moneys via vouchers. There'd likely be a tantrum about religious oppression, but, really, man and dinosaurs, contrary to the teachings at many of the churches and Christian academies around here, really didn't live together [1].
[1] Ok, in the conventional sense of dinosaurs, not the XKCD sense of birds as living dinosaurs. http://xkcd.com/1211/
