Many Christian parents are very sheltering of their kids and if your wife isn't tolerant of that, I fear she may be in for a shock! The parents are paying, I assume? If so, then they are the customer and your wife's tolerance or intolerance is irrelevent! They don't even have to explain or give the reasons for their objections!
From a purely business standpoint, the parent had the right to ask.
Don't hit me with anything!!! ;-)
That's not my point (or my wife's). And actually it may be the school that is in for the shock. It's one thing to not want your kids to read certain things. And like I said, the reading list was a suggested list. They are free to read anything they choose. She was given some guidelines by the school administrator, and she has stayed within those guidelines.
I have trouble with labeling things "Christian" just because. And especially have trouble with accepting the mediocre just because it's "for the Lord."
She IS teaching things from a Biblical world view. But it's simply fantasy to deny that sex, drugs and rock and roll are happening. And, by the time these kids are in the 10th grade, they should be making some of those value judgements on their own.
IMHO, anyone who asks if a suggested list of reading materials is approved for "Christian" families has a very small world view.