You're forgetting a very key thing about this: elementary aged kids tend not to think about sex. It comes about in middle school more when you start thinking about it. Did you choose to be straight?

another key term: realize. I knew I was gay but I didn't accept it. I was told it was wrong, it wasn't right. I didn't even know people were gay until 8th grade. I fought against myself. Then I finally accepted it. This is why I don't ask for people to accept it, because I couldn't accept it myself for a few years. I just ask people to not say things they are not sure about.