I think, if my child was getting acceleration and is doing well, I'd let it go. Is it really about the grade or the process? Is she absorbing the information? And no one will really care later if she got straight A's in elementary. Maybe even push it along to another level because the test is too easy? If it was harder maybe she would slow down? Or double check the concepts against another cirriculum?

I get excited when the library lets me know my books are ready for pickup...