Lots of good advice and questions above... which may help more than the thoughts that keep running through my mind when I read your posts on this topic.

Is there any possibility that she has checked out mentally from class due to it being too easy and is thus not paying enough attention to do well? Or has developed a habit of rushing through work for the same reason?

We did see some of the latter in ODS, which has required a mix of a better fit and encouraging him to show his work/manage the detailed steps.

Has she participated in any academic enrichment outside of school? If so, what's that experience been like?