So whats wrong with school vouchers? Schools get a minimum dollar amount from the government, then for each student enrolled, get some other amount. Allow students the freedom to enroll wherever. Schools that are able to attract many students will have more income, hopefully allowing better teachers, curriculum, whatever. A specialized school with high standards could also attach a surcharge to the money from the voucher (unless its a religious school, church and state and all that), so the "elite" can still be elitists, especially if there is a scholarship program available for those with spectacular ability, but less than spectacular finances.
If you want to go to a football factory, go, get your low education degree, but high football degree, and good luck in life. If you want to be a doctor, go to a school that specializes in cranking out doctors. If you are an "inner city kid" and can't go to anywhere but your local school, guess what, its going to have lots of "inner city kids" going too, which means its going to have lots of money from its vouchers, and be able to hire enough educators, which it can't do know.
and i guess it would help to know if you are referring to private schools in this example as that makes a substantial difference when it comes to vouchers.
I'm not going to claim this doesn't have faults, it does, but it seems far more effective than educating to the lowest common denominator like it feels like public schools do now.