When I was in 4th grade, I was made to read "Sex & Love in Plain Language." A horrible book by today's standards, especially in regards to homosexuality, which was described as a "phase" and a "choice" and a section I read over and over. When I was done reading it, I had a test. It had diagrams I had to label, true/false questions, multiple choice, and an essay. The thing is we were all proficient in the particulars of sex, but the nuances were lost on all of us (4 boys). However, when push came to shove, my coming out, one of my brother's condom wrappers being found in the car, she turned back into a mother right quick! Today, though, it ain't nothing but a thing.
I have this unique ability to recognize an actor who's klingenspritzer I have seen in another movie. We were watching a movie and I shouted out, "I have seen him nude! Who is he?!" My dad turned a shade of red I have yet to name and my mother said, "Oh fantastic, I have a son who can't remember someone's name, but knows their penis on sight." My partner just laughed because I do it all the time at home.
My dad is still very much a prude, yet loves walking around in the nude, which I had to prepare my partner for...just in case. To me, it demonstrates the difference some make between being nude/seeing nudity and sexuality, but it also shows how they can easily get mixed in a negative way. Really, what is the difference in seeing a nude statue and a movie where a woman changes her clothes and you see her breasts? To me there isn't a difference, but for some, it makes a huge difference.