Fine, we can disagree. However please remember that what some people call teaching diversity others consider indoctrination. I am confident enough in the critical thinking skills that my children possess that I wouldn't consider such a curriculum a threat, but others do not have such confidence, nor might their children have strong critical thinking skills.
I'll give you an example. While my oldest was still in the public middle schools he had a teacher that taught that over 10% of the population is homosexual. This was a social studies class and the subject was appropriate and well taught. My son countered with statistics from at least 3 secular organizations including the American Psychological Association which were peer reviewed that demonstrated the percentage to actually be much lower. The teacher refused to allow such information to be presented to the class, refused him the opportunity to make his presentation and instead simply didn't permit him to complete his assignment. (she didn't count the points against him) She told him that they would just have to agree to disagree. Now my son didn't question morality all he did was present alternative statistics from reputable sources, yet they weren't allowed. In fact part of my sons presentation was meant to address the prejudice that homosexuals have been subjected to over the course of the past several decades. My son was able to understand that the teacher had an agenda and let the issue die. Not all students have this kind of self confidence. More importantly no other student in the class questioned the 10% statistic that the teacher presented.
Some parents would see such behavior as indoctrination. I consider it simple ignorance and after all even teachers and curriculum authors can make mistakes but I would not oppose parents having their children excused from such classes.
But like I wrote earlier, it's ok that we disagree, your posts are usually thought provoking at the least, and I enjoy reading them.