The students escaping the ghetto will still be getting a measurably better education on the strained suburban school than they will at the ghetto school they're currently stuck in.

What about the kids who go to the suburban school? Kids from the ghettos can simultaneously be the victims and causes of the state of their school.

Just an anecdote, I went to an upper middle class suburban high school. The poorest kids in my school were the biggest bullies and class disruptors.

Does "escaping" imply segregating one's child from the "ghetto school"?

All parents who love their children would "segregate" them from awful schools if they could. The whole point of thread originator was that geographical restrictions are more unfair to the poor than they are to anyone else.

A modern school can be built in a couple days with modern portable classrooms: http://www.modulargenius.com/portable-classroom.html

Is there a warehouse where you can order a bunch of portables like you can USB cables off of Amazon? No, prefab doesn't mean prebuilt. And that still doesn't cover funding, staff, and all the various local, state, and federal rules that make a school. Buildings, the US has plenty of.

If you have somewhere to put it.

And can find and afford a whole set of qualified staff to teach and administer it.