It is the policy of my school that teachers cannot assign homework due on or immediately following any religious holiday or ceremony. Because the school has a religiously diverse student body, this can sometimes be a planning nightmare. I was initially worried after assigning a project that was due on a day I thought was religion free:
Mr. F: "Where is F? He isn't here to hand in his project?"
R: "Yeah, he's not here because he's practicing his freedom of religion."
Mr. F: "Oh no! Was today a holiday I forgot about? I was so sure it wasn't..."
R: "Well not exactly. He just texted me and he's at home religiously observing his XBox."