SAN FRANCISCO (KGO) -- The only all-male Catholic prep school in San Francisco is dealing with a scandal right now.The ABC7 News I-Team has interviewed teachers at Archbishop Riordan High who say the principal showed them pictures of naked women and other images not appropriate for a school environment.We asked one Riordan High teacher how something like this is brought up and they said, "'Let me show you this, look at this, what do you think about this one?' That's how it comes up. Casually, you know. Like it's no big deal."Even more sensitive, two teachers accuse the principal of showing them a racy video involving a Riordan High student. The school says it investigated the claims twice and they are false.The I-Team investigates what really happened and will air the story on ABC7 News at 11 p.m. Thursday. You can watch the story online or on your