Heartmom... I like your idea of drawing clothes.
You reminded me of waaaay back. I was in 6th grade. In my art classroom there actually a poster on the wall of a greek statue. Of course no clothes. So I cut out some little white boxers, drew red hearts on them and taped the new skivies to the poor guy. My art teacher never took them off of him either. LOL. Wow... public schools and their nekkie pics on the wall. It almost.... aaalmost.... seemed normal to my desensitived mind. So glad to be homeschooling my children! That greek statue wasn't near as bad as what I saw some of the other girls drawing pictures of.
It might be a good thing to teach your kids, "hey, I covered this pic up because I found it inapropriate. You can do that too, if you come across something gruesome or crude. We hide our eyes from evil".