Not sure why a female or a male seeing a penis is harmful for them or dangerous. The only reason why it would be is because they were told it was harmful for them. Seeing people naked is not harmful.
If your daughter understand body parts and showers around body parts they will be just fine and unharmed.
Are you afraid of your son showering near a vagina? Are you afraid of your son seeing or being around another penis? Are you afraid of your son or daughter seeing knee caps, ears or even heaven forbid a tailbone? Body parts needing to be covered up is simply arbitrary. Other societies have deemed different body parts as something to be hidden. Our society didnt use to like men having their shirts off because they found it offensive to see topless men. That changed and no one blinks twice when you see a man at the beach with his top off. Just like in societies where a penis or vagina uncovered is no big deal, no one reacts when they see one or cares.
Maybe parents should teach their kids what the body parts are and use their correct names. Teach them that they are allowed to pick who touches their body and who doesnt. That each person can choose who they are and what they do and to each their own. That every person and every body deserves respect and that they are all different and unique and that is okay. Teach them to respect themselves and others. Seems like that would solve most our problems with these "issues."
In jr high kids are mean and make jokes about bodies. This is due to our society and parenting. Additionally in jr high and high school the kids who are sexually assaulted and who are teased are most often boys doing it to other boys. Girls also do it to each other. Most of the boys and girls teasing and doing the assaulting are straight as well. So if your concern is about your kid being teased or abused then having a trans gendered kid (which is highly unlikely) around has very little possibility if any of them teasing or abusing your kid. It is far more likely with kids that the odd one who is uncomfortable with their body and feels out of place is going to be abused and teased. The minority group does not generally abuse the majority in kids locker room.
I do believe our society needs to relax about bodies and be more comfortable with their own bodies and bodies that are different from theirs. Group showers should not be an issue. But if a kid is uncomfortable of other kids and/or teachers they should be able to go into a shower that is private. The expense to build a shower with stalls would not be that much more if any over group showers.
Additionally @
Joe Bagadonuts you said society is heading the wrong way with protecting or being concerned with this small minority of trans gendered people. That statement has is the opposite of what it should be. The majority do not need to be protected, they are the majority. The rights that need protection in society are the group that is abused and hurt the most which is minorities. I am shocked someone would feel the opposite. White males, especially Christians, in our society have by far the most advantage and are the least abused of any group. Their walk in life is so much easier than everyone else's as a whole. Pretty sure that the number of white, straight, Christian males that have been abused by a trans gendered person is as close to 0 percent as possible. I am also positive that the majority of trans gendered people have been abused, teased or made to feel bad about themselves at least once on average by a straight white male.
The trans gendered issue inst about safety of your kids or women in lockers/showers. Abuse has been happening and is going to keep happening and the people doing it are rarely trans gendered people. This issue is about being uncomfortable with someone different and not respecting the rights of someone that has a different life style from your own.
If we want to talk about sexual assault and how to solve that then it is a different topic. One that revolves around boys growing up with a lack of respect for women and viewing them as objects and has nothing to do with where a trans gendered person goes to the bathroom.