In many instances, the issue is not the school funding, but who the students are. Many inner city schools receive literally twice the funding per pupil as adjacent inner-ring suburbs, but if the suburban town is the one where college professors and highly educated professionals choose to live, the school districts tend to be very high quality, because the kids are like their parents, and the parents have high academic expectations of the kids.
I think that parents coming from certain countries where there is a strong class divide expressed in the private vs public education divide wrongly assume that they need to pay for school. We all know that that is NOT true in the US, especially when the family is going to be living within commuting distance of a university, and will have the option of renting in a district with good schools. Certainly, with two kids, the bill for private school for both together would be somewhere between 110K - 140K/yr. That is far more than the cost to rent a palace in the town with the best public schools, near the parent’s university.
Frankly, if they have that kind of money to spend while earning only a grad student’s stipend, they wouldn’t be on here asking.
As for music education, unless we’re talking Interlochen boarding school, a local conservatory’s precollege program will offer broader and more in-depth music education than any boarding or private school possibly could.
I agree - the first step is for the parent to nail down the university, and then investigate public education in the area (and private options, if they have the means).