Of course I think SAS Puxi is very international. I’m not saying that it’s like an US army base school or anything. It has wonderful diversity. However, my reference to its isolation is based upon the actual layout of it campus in relations to its surroundings (especially if your look at its Pudong campus).
I think the larger issue is that for nearly all the int’l school students in Shanghai, they lead a privileged, expat life devoid of any meaningful interaction with locals, apart from those who do menial labor around them. The only way to avoid this is to send the child directly to a local school; otherwise the supercilious attitudes adopted by most expat kids will remain.
Regarding SCIS Changning:
I must again reiterate I am trying to be as objective as possible, but my familiarity with elementary schools is far less extensive. (I taught high school). I will only say that the Changning campus is actually also very close to the center of the city, but it doesn’t offer upper grades at this campus.