If OP was Muslim and gave that as a reason, I guarantee you would not be seeing the same people on here saying "let it go".
Religion does massive harm. Especially Catholicism and it's branches. Telling kids they're being constantly watched and judged against a set of values from 2,000 years and they'll suffer an eternity in hell if they don't toe the line. Why would you subject your children to that?
Even the story of Noah's Ark is about a deranged psychopath who killed everybody (animals included) with the exception of an elite few just because he flipped.
You either believe that story is true, in which case you're a psychopath yourself. Or you don't, in which case there are many better examples of morality to be found elsewhere. It really has no place in modern education (or life) other than simply to discuss as an example of the nonsense humanity has peddled.
It gives a warped world view of right and wrong, science, history, and nature.
I'm completely with you, OP. Kick up as much of a fuss as you can.