I really like http://www.systemath.com for those years. It is not a flashy program, but it does a really good job of explaining things. The Systematic Mathematics program goes through Algebra 2. I am going to use this or continue with Math u See.
I may be wrong, but Charlotte had children doing more traditional math by 7th grade. She had longer lessons too for that age (30-40 minutes, I think).
Singapore is a solid program, but I know nothing about the NEM books.
Hopefully, someone will chime in. 🙂