These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: The History Boys
Ho Yay: Everybody/Anyone. It's set in an all-boys school and the whole class has great rapport (and are mostly Bishōnen), so any ship floats, despite the fact only a handful of characters are explicitly gay.
Tear Jerker: Hector's funeral, where the boys sing "Bye Bye Blackbird" and Ms. Lintott monologues about what happens to each of them in the future.
Unfortunate Implications: In the stage show, Posner - the unambiguously gay character - ends up failing at university and living as a recluse for the rest of his life, assembling scrap books of his classmates' achievements and posing as a women on the Internet. The ending of the film is a little more upbeat.
On the other hand, the film ending has Posner admit he too desires some of his students even if he doesn't pursue any relationships with them which carries an implication that All Gays Are Pedophiles. It would have been better left off with Irwin and Hector only and all the ambiguous morality that accompanied them.