I can’t believe I never saw this! This interactive graph looks at reviews by gender of the teacher and subject and tells you how often they’re used.
It gives some interesting results. “Demanding” in almost every subject is used more to describe women than men. Same with “easy”. “Fair” is pretty even, but “unfair” is once again used to describe women far more than men. “Good”? Uniformly men. “Hot”? Mixed.
I’m having way too much fun putting in terms.
Edit: more interesting but mostly unsurprising terms: “strict”, “biased” (also fun to sort that into positive reviews only to see the change), “love”.