L.G.
As a high school math teacher, I am curious as to why you want her to take pre-algebra over the summer. Does math come easy to her and she wants to get ahead? Or is this a review of a class that she had last year or a preview of a class she is taking in the fall? I would support any of the above. If this is to replace a year-long course and math doesn't come easy to her, I would not recommend she take a condensed course in the summer.