Hi Twinkle, your DD sounds similar to DS1. He's just started Reception (in a great local village school) and is loving it. He does find it all quite tiring, but he's doing so much better than I would have thought a couple of years ago. I think if you find a good school, then they should be able to identify and differentiate for a bright child. Personally, I think it's quite hard to ask questions in advance, at an open day - I'm not saying you shouldn't try, but when they don't know your child yet, it's quite easy to come across as a bit of a pushy parent (and hard for them to know what to answer anyway). With DS, we had a home visit from the class teacher a couple of weeks into term (not just us, everyone did), and that was the time I felt I had a proper conversation with her, because by then she'd really got DS's measure!! (At the open day, I'd asked her a couple of questions, but I felt she was a bit cagy/wary - but actually she's fantastic.) So although it's worth asking some questions when you look round (e.g. about whether there's official 'streaming' in the classes, or how they differentiate), you might not get terribly useful answers.
The other thing to remember is that school is about SO much more than learning, particularly in the first year or two. I've only really realised this in the last couple of months. And I'm quite glad that DS is finding all the 'work' pretty easy so far, because it's one less thing for him to worry about while he's getting used to all the other stuff (being independent, choosing his own lunch, being around older children etc etc etc).
My other question is whether your DD goes to a preschool at all? DS1 started when we was just under 3, and it made all the difference with him. Until then, he'd been so socially awkward that he really didn't interact with other children at all, and for a long time we were quite worried that he was on the autistic spectrum. But he really blossomed at pre-school (it still took a while, but it happened), and when it was time for his first day at school (a day I'd been dreading for years, TBH), he was completely fine. He's still no social butterfly, but he's made a couple of new friends in his class already (who seem to like him too), and he comes home telling me he's been playing various inexplicable running around games in the playground, which I take as a good sign
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