SF parent here.

The original idea was to mix up the student diversity. Poor kids would sometimes attend schools in expensive school distracts - Kids from expensive neighborhoods would attend poorer schools.

Hilariously not thought through. (just like rent control). All that actually happened was the rich kids yanked their children out of public school, the "in the middle parents" put their kids into catholic school (which is 1/5 the cost of private here). The poor kids then had to beg their parents to get across the city -- WHICH THE PARENTS could not. What a mess.