Pointing out the law, in practical terms, is of little use when it comes to managing the interests and realities of diverse families. In my experience, you have to listen to parents, whether they are loud or not, and consider the restrictions of the school itself, at the level of people and organization. With that you identify common ground and can generate changes. Not all achievements are for the direct benefit of one’s own children and some are reflected in the medium term, but you build community and traction to bigger changes.