It is probably unusual to have a course section with a minimum median income of $120,000 even at Harvard.
The median household income in Cambridge, MA (the city where most of Harvard's campus is) is $83,122 [0] and 8.4% of families and 14% of people live in poverty.
The source [1] the author links to regarding student family income at Harvard shows that 15.1% of students come from the top 1% (which I guess means top 1% in terms of national income). It's a good read by the way.