I'm not Catholic Christian but Protestant. You should be yourself and let people know what you believe, When someone tells me their atheist I don't get all religious on them. Not EVERY Christian is a stark raving mad dog that wants to eat you alive, though you seem to be in a Catholic school and I have no idea what the Christians are like over there. But, I still think you should put it how it is and not worry about how people think of you because of what you believe, It's easy and really, do you care what your Catholic peers think about you?