Smart parents will do their best to send their kids to private schools, but the less fortunate kids will get stuck in public. If it were even easier/cheaper to send your kids to private, then there would be an even greater separation between the kids who's parents care and the kids who's parents don't give a damn (the haves and have-nots).
The answer isn't to make more private schools, the answer is to fix public schools. And the problem with public schools is not the teachers. The teachers are working within a system that is broken. Rather than go into the details, here's a quick example: you're a teacher. You cover the material in class. You're inventive, dynamic, clear, withit, the whole nine yards. You assign homework on the material, go over the homework, and then give a quiz (on that material). Students fail because they didn't study and don't care (and this stems from most parents not giving a shit about school as long as their kids are out of the house and having some fun in sports). You go over the quiz in class, and give a test later in the week (on the same material). The students fail because they don't care and didn't study. You have a choice: do you fail a bunch of students and bring down a shitstorm of parent complaints and administration complaints? Or do you yet again make things even easier and maybe even curve the grades so only the very least prepared students fail?
If you fail a bunch of students, administration will claim that you're a bad teacher. You'll have constant visits by "guests" (from administration) in the back of the room evaluating you. Parents will complain loudly that you're inept. Everyone will turn you into a scapegoat. If you're not tenured, you're gone.
Let me give you a hint: teaching is just a job, like any other job except that you're helping kids and so you try to go the extra mile if you can. But it's still just a job, and its not worth all the shit you get to make it rigorous if no one else is doing it, if you get no help from administration, and if you in fact get severely punished for it.
You want to fix education? Let the teachers teach, and let them fail students who fail. And for Pete's sake, get rid of the fucking standardized tests. They turn education into color-by-numbers.