Sister Schools?

Lunched yesterday with a nice young CPA from Hyderabad (by way of Australia, Canada, Boston) recently settled in Morrisville. Having people like that move to the Triangle and to America is a good thing. At the same time, there is truth to the "bubble" meme, i.e. coastal elites are cut off from parts of the county that are hurting. The concept of "sister cities" around the world was once popular. Today, why not have "sister cities" or even "sister schools" that are closer? Have affluent public schools develop relationships with specific, less-fortunate schools not so geographically distant. Have affluent PTAs raise money for them, I know there are downsides (seeming patronizing, exciting envy, etc.) but might there not be value?