Unfortunately for some people who start off buying or building a home in "a perfect school area," things do change. The home you buy now could be "rezoned" into a different district by the time your kids get there (which may or may not be a good thing.) You might end up having an unexpected job change that causes you to move between now and then. My point is, there are no guarantees.
I know that the administration can influence the overall tone/attitude of the teaching staff, as well as the students at any school. If you get a new superintendent in the district, or a new principal at the school, who is responsible for hiring new instructors, or using a different curriculum, you're apt to see quite a few changes. The fact that people already recognize the school has shortcomings sounds like a good step in the right direction.