One of the most engaging features of Diane Ravitch’s infuriating book, The Language Police: How Pressure Groups Restrict What Students Learn, is the appendix, where Ravitch, a New York University historian of education, lists words and topics that de facto censors, both left-wing and right-wing, have effectively removed from textbooks and tests used in public schools.
Snowmen should become snowpersons but should probably not be mentioned at all, as children from warm climates who have never made snowmen are at a disadvantage in tests that mention them.
Kelley T. The Language Police: How Pressure Groups Restrict What Students Learn. Arch Pediatr Adolesc Med. 2005;159(3):301. doi:10.1001/archpedi.159.3.301