[danaris]

Almost all of the success of private schools is, in fact, the former. Being able to select who goes there basically lets them set their outcomes.

[mmcdermott]

To a degree. There's some sampling bias as well because the kind of parent that would choose a non-default education option probably cares more to begin with.

[Cupertino95014]

You mean, the kids won the Genetics Lottery?

Yes, getting born with parents who care about you is definitely a smart life hack.