A blog post by Kaihan Krippendorf on the Fast Company site makes a valuable point: that it is not enough for someone to like (or even love) your product. Customers also must need your what it is that your school does for them.
We talk with hundreds of parents who like their independent or international school just fine, but they don't really need (or know they need) it enough to stay laminated through thick or thin. So when tuition rises, or their child's 3rd Grade teacher is less than perfect, or the sports program seems inadequate, it becomes all to easy to switch schools to another one they like just as much. Switching becomes much, much harder when the relationship is based more on need.
Maybe the first marketing question you ask shouldn't be about what features and benefits to feature--everyone will have much the same list--but about how to turn your school into something its families need, even if part of your work will be to help them understand how much they need it.