You’re joking right? The reason private schools are good is because nobody would pay money to go to one if it sucked. Crappy private schools don’t succeed, but public schools can blow donkey nuts and they keep getting budget increases from our wonderful government anyway.
The parents sending kids to private schools already pay school taxes to fund the public schools (which suck). The parents choose to pay for school twice, so that their kids can get a better education. The real answer would be to eliminate teachers unions and tenure, and to allow people to choose which public school they wanted to attend, rather than forcing them to attend a certain one based on their physical address/zip code.