Hi @lifeiyu, for Math specifically, one thing that may help before choosing more resources is to first identify what kind of mistakes your daughter is making.

Sometimes students keep doing more TYS, but the issue is actually an earlier weak foundation, method choice, or repeated careless pattern.

I’m building Mentora, an online E-Math diagnostic/practice tool for Singapore O-Level students. There is a free diagnostic here if you’d like to try it: https://www.mentoraedu.tech/free-diagnostic

It is meant to help students find the weak link first, then practise more deliberately instead of just doing more papers blindly.

Separately, for free resources, Holy Grail and TYS explanations are still useful. I’d use those together with a short diagnostic so your daughter knows which topics to prioritise.