I think that they encourage competition as a way of motivating the kids. I think it's a deliberate part of the exercise.

If having my daughter try some of the things already suggested doesn't solve the problem, then we may have to choose between asking them to let her work independently or asking them to make the projects less competitive. I think they consider it very important, though; part of their charter is project-based learning and they may not want to make changes for one child.