One cannot judge the success of a school or student (or a president!) without prior agreement about what we mean by success.
We're talking about public schools, after all--and the public has a right to demand certain results from its investment.
We need schools that define success in broader ways than test scores or college completion.
We have a whole class of children growing up without fathers, and they are doing terribly.
How do we sustain good schools so that over time there are more and more of them? I think networks of schools are a useful added component.