Extra help for GGD in school

Let her stay as she is she sounds happy bright and full of life why change that for a more Academic perhaps unhappy time
She will find her own future and there is so much more to life than maths and English keep your money and if she needs some private tuition when it comes to exams you can help that way

She sounds as if she’s got a wonderful future perhaps in swimming, sport or who knows, the worlds her oyster if she has enthusiasm for life Don’t try to change her

Depends a bit on the school. Those schools that are highly selective and trade on their exam results won’t be keen to admit a child who is likely to do less well at GCSE and A Level. Many do not admit children who need one-to-one classroom support. Some are delightfully supportive places with small classes and out-of-the-classroom learning support.

If she’s happy where she is and getting appropriate support, I’d leave her where she is. You could spend tens of thousands of pounds making her less confident and rather unhappy in pursuit of academic goals she cannot achieve.