A school is fundamentally a social environment - children are legally compelled to be there, and the specific educational structure is centered around being forced to be in classrooms with large numbers of similarly-aged kids, for large portions of the day. Much of what one learns in school is social acculturation to the specific segment of society represented by the other kids there, rather than the contents of classroom learning.
How good a school is - which we can expand into more detailed definitions like "how much do children learn there?", "how much does any individual kid like or hate it?", "is this a good use of a child's time?" - is dominated by what the other kids they are in a shared social setting are like, and not by how expensive the facilities are or how well the teachers are paid.
How good a school is - which we can expand into more detailed definitions like "how much do children learn there?", "how much does any individual kid like or hate it?", "is this a good use of a child's time?" - is dominated by what the other kids they are in a shared social setting are like, and not by how expensive the facilities are or how well the teachers are paid.