What’s my idea? Since you asked, you’d start with magnet school applications. No base assignments prior to that. Kids in magnet-base neighborhoods could apply for the base seats in the magnets; all students, including magnet-base kids, could apply for the magnet seats, but selections would be made so as to assure that the magnet seats go to high-achieving students.

I think it wold make sense then to begin filling STEM schools and the leadership academies by a similar process, being sure that diversity standards are met for each, before making base assignments. The reason for holding off on base assignments is to create the maximum possible availabity (slack capacity) in the non-magnet, non-STEM schools.

After that, you make base assignments, grandfathering all students into their current schools if they want to stay or into their current feeder school if they’re moving from ES to MS or from MS to HS. If they don’t like their current school or feeder assignment, they can enter into a choice process for seats in schools with excess capacity; this would be a rolling process in which the first students moved would be the ones in crowded schools who apply for seats in schools with excess capacity. Again, diversity standards would be established and upheld; no moves would be approved if they’d bust the standard.

But here’s a fundamental problem that I’m not sure can be bridged. Under an address- or base-assignment plan, when a new school opens, kids are assigned to fill — they’re reassigned, in other words. Under controlled-choice, new schools are filled gradually and by choice; no one is reassigned or forced to attend them. By the same token, existing schools may be under-enrolled, probably because parents see that they have a lot of poor kids in them and/or their test scores are low. What do you then? You’d better do something, because if nothing’s done, an under-enrolled school this year will almost certainly but even more under-enrolled next year.

The first way, filling new schools by reassignment, is efficient and saves money. No school opens with less than a full student body. No matter how mad it makes parents to have their kids shuffled around.

Even under controlled-choice, though, when the desirable schools are full, unlucky kids will be forced to “choose” from the rest of the list. Not only that, but the choice lottery may put a child in one school and his next-door neighborhood (of the same age) in another school entirely. So not only did you not get a school you wanted, you aren’t even assigned to the same school your friends go to.

So when new schools open, I’m thinking that you need to fill them as much as poss