Well, on the narrow legal grounds of the law, I would probably agree with the court's finding that there's no "no such specific right can be found in the deep roots of the nation's history and tradition or implied in the concept of ordered liberty." Of course, substitute "Roe v. Wade" and then all of a sudden they don't have any problems whatsover finding the specific right. Of course, they don't have the intellectual honesty to admit this, but that's another story.
On the political side of it, on the practical side I agree that parents shouldn't have a veto right over portions of content, you can either accept or reject the entire syllabus else it's a license to micro-manage everything the teacher does. But on the other hand, not even mentioning on the consent form that a sex survey was part of the ciriculum for an first grade class would be termination grounds if I were the Superintendent, and grounds for impeachment of the school board if they supported this activity. There is no legitimate state interest in conducting such a survey that I can possibly think of and this is one of the worst lapses of judgement by an education system I think I've ever seen as a citizen.