I have been quite impressed with the quality of Catholic school students and home school students. I think it is significant the number of home school students who perform highly at spelling bees and geography bees.
I still believe that contrary to assertions in this discussion that many private schools encourage an understanding of evolution and various explanations of nature's order. In my experience in teaching, I have not noticed Catholic students to be less receptive or less interested in science.
You haven't noticed it because it doesn't exist. There is a group here at FR who offer the argument that believing in creation is somehow a detriment to ones abilty to learn science. It is nonsense of course but they argue it nonetheless.
That's my experience, too. The religious/home school kids get all the knowledge about evolution so they know what it's all about. They also need it for standardized testing. Some states, I think, include it on their standardized tests. (Unfairly, I think, if the questions are worded in a "loaded" way.)
Thank you for being a teacher.