There are indeed studies that support
@K-Dog 's point of view that private school is better, but I tend to disagree with the premise of one of the underlying data points.
Most studies supporting private schools, that I've seen, say that private school students have a better chance of getting into college. That is true. On the surface, that would indicate that the education is better. However, public school students, by comparison, do as well or better than private school students in terms of academic achievement, as evidenced by the story I shared above. What does this mean, if two groups perform equally on standardized tests but ascend to the higher level at unequal rates?
It means that, ultimately, the barrier to higher education/trade school/vocational training isn't grades but money. So I would argue that families that can afford send their kids to private K-12 can also afford to send their kids to college. It's a matter of money, not education or achievement. This is why I support free, or at least heavily subsidized, higher ed and job training. There are smarter people than me that are unable to afford even community college. That's a spit in the face of the American Dream. The American Dream is dead because you have to pay to play.