We seem fairly evenly split, don't we?! You're going to have to follow your intuition... But my 2pworth is that he sounds in need of more challenge rather than of a diagnosis - I'd wonder whether the gifted class is almost as underchallenging as the normal classroom for him (might be worth a fuller investigation of his level of giftedness). You said that it can't all be boring and that e.g. he doesn't write much even for interesting writing tasks. My DS's teacher last year had what seemed to me a useful insight when he was behaving similarly - she said that he wants to write things that are like what he reads in books, isn't prepared to be satisfied with something that seems less convincing that that, and gets frustrated. Maybe it's similar for your DS?

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