I don't think you need to tell boys to have boners. Human nature is curious by design, not by social construct. Men like looking at nude women, which again is nature rather than nurture. As to the point of your teacher being naked and spread eagle all over the web, I think it undermines your academic gravitas and makes it hard to teach teenagers--or adults for that matter--if everyone is aware you have a shaved beaver. I'm not disparaging sex workers. Live and let live, man. But most female teachers I know would prefer to be taken seriously.