I totally agree with you Mia and my DS7 is exactly the same - vastly further ahead in reading than math, although really I think math is going to be his strongest area at the end of the day.
It's much easier to have exposure to a lot of different reading sources than fill holes in math. I have DS working 3rd grade math right now (going into 2nd), and it's filling holes. A lot of it he really does "know" conceptually but maybe isn't familiar with notation. Ah ... one of the things we hope to fix somewhat by homeschooling. Anyway - it's much more about how they learn, rather than what exactly they know IMHO.
