Some public schools are just fine. Some private schools are awful given who my kid is. I just want to know which one is which.
In other countries like Finland, they have it right compared to US education system the genius W contributed to breaking: homework has no value, teaching answers to excessive standardized tests (NCLBA) has little value, and grading teachers on immediate performance of said standardized tests has little value.
To solve this problem of finding good schools, I believe word-of-mouth advice from more successful folks is more valuable than any website filled with sour grapes or unverifiable claims made by random, anonymous people. It also can be a problem that better areas tend to have better schools, so no website will be able to find what doesn't currently exist in low population or not-as-nice areas.
There are websites like USNAWR who attempt to rate K-12 schools, private and public. https://www.usnews.com/education/k12
the problem has multiple aspects. funding is one, management another, actual teaching methodologies yet another. for all of those examples can be found. not everything is directly applicable and it takes some experimentation.
but a part of the problem is also the definition of success. the goalpost on that keeps changing too.
for adults to be successful the environment needs to be supportive too.
aren't there studies that show that children from poor families are less successful despite good schooling? so if we want children to be successful we also need to eliminate poverty. these things go hand in hand. and i suspect that some attempts at better schooling fail because other aspects like this are not being addressed.