School districts are often supersets of municipalities.
This is the correct answer.
From RFC 1386, Section 3.3.1:
"Public schools are usually organized by districts which can be larger or smaller than a city or county."
alt Hacker News
This is the correct answer.
From RFC 1386, Section 3.3.1:
https://datatracker.ietf.org/doc/html/rfc1386#page-12