I agree, definitely a misunderstood right, very sticky and difficult to resolve fairly. What galls me is how, since the teacher is liberal and the parents conservative, everyone on this site immediately agrees with the parents. It should not be so one-sided; if it is such a sticky issue, both sides are entitled to their free speech as well as their right to disagree with others. However, it seems that the parent’s right to free speech is greater than the teacher’s.
IMO, the teacher had the right to post what she did - considering the lack of identifying facts - and the parents had the right to disagree. They asked her to take off the blog, so she did. Justice served.