FAME
An offshoot from the eternal question: what exactly defines a musical in terms of the relationship between music and drama? I’m not convinced that this particular film can be called a musical, although the stage production sharing the same name and title track certainly is. Perhaps the best way to classify Fame would be to call it a pseudo-pop-dance-musical. Whatever it is, it is messy somewhat contrived, senselessly (and at the same time unavoidably) episodic: it really gets by because the cast is so committed to what they’re doing and because of the way it captured the spirit of the 1980s so perfectly. In the grand scheme of things, Fame most likely will be a footnote in the canon of movie musicals, along with Footloose, Dirty Dancing and Flashdance and the somewhat thin debate surrounding their classification.
Musical Cyberspace 
Fame is not a movie musical. It is nothing like a musical other than it shares the same name / basic plot with one. It’s just a film with a soundtrack, n’est-ce pas?
Yes, it is. Several characters sing in it and the stage musical is based on the film.
What characters sing what original songs? I don’t see that as a movie musical. It has to actually have character singing as if they were in a musical (in a movie) for me to consider it a movie musical, otherwise it’s just a movie with singing (like Camp or Sister Act II). That’s like saying Shakespeare’s Much Ado About Nothing is a musical because Balthazar sings in it.
Hey, 8 Mile was counted as a musical in the UK run-down of the greatest musicals.
Fame is a movie musical! There isn’t many musical numbers, but there is a few! They are all singing “Hot Lunch” in the cafeteria, Coco sings a song at the piano with Bruno, Montgomery sings a song at his apartment and the entire cast sings “I Sing the Body Electric” at the end of the movie! I know it is only a handful of numbers, but I believe it is a musical nonetheless!
Which of those are book songs and which are diegetic songs? In my opinion, a musical is defined by containing/relying on book songs.
You don’t know what you’re talking about. Take a seat. Thanks!