You might mention the possibility that the rest of the textbooks used by this school might be similarly inappropriate for the courses necessary to graduate.
I attended a Christian High School for three years and transfered to a public high for my last year. I had to take summer school classes to get the courses necessary for graduation. Something to keep in the back of your mind. My mother never checked and if I had stayed in the Christian School through graduation, I would not have been able to go to any college except the same denomination's Christian college. That was not deliberate on the part of the school, just ignorance of state requirements.
This is what I just posted over on a religious thread.
I give up. So much for trying to do the right thing. If I can't even get my own husband on my side then I've lost.
My own husband is not even on my side on this issue. He hates the book and wants it out of the school but says I went about it the wrong way and I need to put out a public apology. Personally, I think the school should apologize for filling our children's heads with smut but my husband says that's no longer the issue. The issue is now the fact that I sent the email out to the parents. This is so screwed up I can't believe it. See what happens when you try to do the right thing? This is why no one wants to get involved.