C.S.
I used Switched on Schoolhouse with my 7th grader a couple of years ago. It's a computer based program. She can get alot of work done in one day. Doubleup assignments, skip to tests if she is getting things easily. That will save time on busy work. You don't have to do every thing. If she gets it, just test her and move on. The public school system should allow her to homeschool during the summer if needed. There are kids to have to go to summer school to pass sometimes. Don't stress out, Let her set the pace, and reassure her she will be fine. If some subjects move faster than others for her, learn ways to "fly through them", for example, if she understands a science concept, skip doing the experiment. The program grades itself most of the time, and keeps up with everything for you. Assignments, grading, and bookkeeping. Good Luck.
There really is no reason to stress.