My year 8 daughter is really excelling in Expanding Quadratics. What should I be teaching her next to boost her?

Basic trigonometry would be useful and would prepare her for her GCSE’s. Also factorising quadratics. Once she knows how to factorise and expanding well then give her questions where she has to use these skills she’s learnt (think gcse past paper questions). I know GCSEs are still quite far away for her but some of the questions are relative simple so nothing wrong with practicing with them.

You could try some trigonometry, I’m doing that with some year 10’s right now who have just before been doing quadratics. 😀