If there were a consequence that meant something to her, she would be more concerned. She knows she can do it. You know she can do it. There's not much potential for intrinsic motivation there.
Even in college, I often rushed through my tests very quickly, since after the test I could be free! Free! I just hated being in the testing room. If I were taking these tests at home, I might be persuaded to do better at them if I were made to stay at the computer for 20-25 minutes (or until I was done, whichever came later), but maybe with an iPod listening to some really good music that I knew wouldn't distract me, and maybe a snack.
Luckily for me, I have quite a collection of what I call "music for quiet productivity". This includes instrumental as well as vocals sung in foreign languages. The music has enough of a rhythm/texture to keep me buzzing on task, but nothing to distract me from the task at hand.
This might also be the time for some limited, positive extrinsic motivation. If she gets 10 consecutive A's on quizzes, she gets to go to ______ or do ______.
