I enjoyed all of these, especially The Breakfast Club (which as you say, is more cult than cheese). :)

I have plenty of guilty pleasure films, but on the specific subject of American High School films from the 1980s, here are a few I think are genuinely good: Lucas, Heathers, Ferris Bueller's Day Off, and Fast Times at Ridgemont High.

And on the extreme cheese pile: High School USA (with a pre-Back to the Future Michael J Fox) - a largely forgotten 1983 TV movie that I saw on VHS.