Her being very happy at school is worth a lot; I'd be reluctant to move her. But maybe a chat with her teacher about how she's doing in school, and go from there? It is really important to have challenges other than perfection on easy work, but don't assume from another school's type that it'd provide that better. Could be the teacher is differentiating fantastically, could be your DD has an unidentified LD that makes things hard, could be lots of things.

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