Hmm... Depends, really. *Does* he understand the material (but make slips in tests?) do you think? What happens when you talk to him explicitly about the need to work and needing to work being fine, etc? I asked my DS what he'd advise (mostly, of course, wondering whether anything would come out of relevance to his own situation) and, interestingly to me, he immediately assumed your DS was just not interested in geometry as things are, and suggested books, e.g. the AoPS geometry book, or DVDs e.g. Great Courses Maths of the Visual World, that he might find interesting. Anything in that? What does he say about it? As a practical matter, I wouldn't let errors in homework go, even if the teacher does.

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