Well, you can send her over here to homeschool math with my 7 year old. They sound very similar. He learned multi-digit multiplication and long division from paying attention to his older sister's lessons...vs. being taught directly. I'm sure they'd have a blast making up problems for each other on our white board.
On a serious note, I wouldn't know what to do if I had a child like this at a public school. I think I'd be inclined to let her do what she wanted and fight the public school to provide at her level, whatever that ends up being by the Fall. You could also throw in some problem solving (check out Art of Problem Solving, Math Olympia, The Math League for resources you can buy) and some other math concepts. Some ideas are converting to and from different bases (binary, hexadecimal, etc), statistics, probability, business math, stewardship, math books like Murderous Math, and anything else not in a typical school curriculum. Perhaps some computer programming might be interesting as well.
