It's a nice thing to know, of course, but I don't see it as much of an issue. My big problem with the AR system (which my childrens' school uses) is that it discourages challenging yourself. They will not even allow a child to TRY a test on a book above their level - although occasionally my son logs in and does it anyway when the teacher is not paying attention. (Although it does occasionally end in slightly lower scores, I'm not going to discourage that). Anyway, I have a "never say no" policy toward reading. I may try to steer them in another direction if they are looking at something that I don't think they are ready for, but if they are really set on it, I let them read it. Most of the time they choose things fairly close to their tested level, but my son did surprise me by reading half of the Harry Potter series last summer - 3 or 4 years ahead of what the AR people say he should be doing. Now he has his eye on my Stephen King collection and is not backing down - at 8 years old, I may have to try and steer him to one of the more "tame" books.
Anyway, I'm rambling. My point is, tell her teacher that if they will not test her, she should not have to do the same work as the kids below her level. Send a book with her to read at school if you have to. But most kids who enjoy reading will choose challenging books for themselves.