Is this the AOPS online pre-algebra class? Personally, I don't love that format for a 9-year-old. They have to type quickly to be part of the "conversation," and the math is hard. When my son did that class in 5th grade, his teacher, a former high school math teacher, couldn't even answer one of the challenge problems! Of course it's designed to be challenging but if my son wanted to take the class. I can't imagine how it would have gone if I would have insisted he take it.
My concern is that forcing her to stick with this class will make her hate math.
I suggest you find something else where she can work to her level. How about IXL, Kahn, Thinkwell, CTY, BYU online, or any of the numerous other online math classes. AOPS is extremely well regarded, especially for gifted kids, but it's not for every gifted kid.
