To Kill a Mockingbird was OK, obviously, and Of Mice and Men, tho' Curly's (?) wife was hardly a role model. TKaM is great, and ticks the multi-cultural box but it's v densely written and a big ask for lower groups. Thank god for the film. I even managed it with the least able group. They were surprisingly perceptive. It was like having a class full of Mayellas. It's only just now that it's occurred to me that it was written by a woman. Is it really relevant? Would it have been different if Scout had been a girl?
I alternated TKaM and LotF, because I like a change. Of Mice and Men isn't to my personal taste. The least good of Steinbeck's books, imo.
But others chose it, because it's short and relatively accessible - league tables and all that. By the time I retired, everyone seemed to be reading it and nothing else. One of the reasons, I suppose, why Gove brought in the English native authors only rule.
I only taught CitR once, in a posh Indie girls' school, mid-60s. Not an exam text. They were enthusiastic but there were parental complaints about the language. 'Crap', 'shit'. As I said, way back, it was revolutionary at the time.
Sorry for the digression. I do know what you mean about your son. I have a teenage grandson and it's great when we agree about a book. Don't think he'd like CitR. He prefers books with a bigger hinterland.