Tuition at the Columbia School of General Studies is $1392 per credit. For a three credit course, that amounts to $4176. If you add a pro-rata share of various manatory student fees, books, etc. the author’s number is certainly in the ballpark.
See this link: http://www.gs.columbia.edu/tuition-and-fees-chart
Somehow I doubt the kids taking this course will have twice as good an education as mine was. They seem to be protesting the wrong people.