How to improve on Math?

I'm an incoming sophmore who's going to take the PSAT this October. I did really bad freshman year (got a 1070) and I'm looking to get a much higher score (the goal this year is around 1300-1400). Remember, this is the PSAT.

My reading/writing scores are pretty good. The issue is Math. I seem to struggle with some parts of math -- not everything. I have just completed Honors Geometry, and I am taking Honors Algebra 2 this incoming year.

What resources can I use to get a much higher score on PSAT math? Any good resources out there? I don't mind the $$ cost.

I've looked at Khan Academy, but the problem is they don't teach the concepts. It's just a bunch of practice problems.