Agree with the other poster on this one. 3 year old, yes that happens. 9 year old? Seriously? 3 year olds have no impulse control and have yet to learn tact. I wouldn't expect a 9 year old to have perfected or have total self control, but enough to not vocally single out another person's body and what they are wearing. There's a huge difference between being observant and being rude. My 8 year old has a pretty good understanding of the difference. She was exposed to speedos and other things on our last cruise. First one she saw walk by she leaned into me and started to whisper (here's where she's learned a bit of tact and by the age of 8 knows enough to not say something outloud and obvious) about what the person was wearing. I stopped her short and explained everyone has a different idea of what is appropriate to wear on vacation. I told her don't be rude and go enjoy the beach. End of discussion. End of the topic for the entire vacation.
So back in the 1920's when women were arrested at beaches for being in long shorts.....how do you explain that? They were pretty much covered head to toe, but because a full dress or something similar wasn't on their bodies they were considered to be scandalous.

It was the times and CULTURE of our country. Other countries during that time women could wear these things and less and it was acceptable. Social standards in this country are women need to be modest and if anything happens to them or is said about them, well then they were asking for it. Saying a normal response for an older child to say something about another person's body and what they are wearing outloud is normal? Sorry not in my house. We're pretty far from being nudists around here too. For one it is like 20 degrees outside, but for other reasons as well.
Isn't some of the point of going on vacation is to enjoy, expose your kids to different things, different cultures and different experiences? I do this so my child won't feel embarrassed or be shocked when she sees something that's outside of her social norm. I do this so she can better function in a global world where every day you encounter different cultural and social ideas and standards. I do this so she isn't rude to people who fall outside of her social comfort zone. I go on vacations like this so I can enjoy a few drinks on the beach wearing a tank top and shorts and be left alone, again unless you want to bring me a drink.
Yes we have dress codes in schools, work places and many other places. In that dress code men are usually required to wear a shirt, yet it's ok for them to be without one at the beach. Why? Aren't they being immodest? Why are parents not grabbing their young girls and running away when a man doesn't have a shirt on? Because in our society it's been deemed acceptable for them not to. I wear long pants to work, should I wear them to the beach too? I wear what I find and feel to be appropriate to different places. If there's a dress code I follow that. I cover myself up on the beach based on what I feel is right for me and my values. In some countries showing my face is considered to be improper, offensive. If you traveled to a country where this is the standard would you plan and prepare to have your entire body, face included covered up at all times? If you knew you would be around others who hold that value would you change your personal dress code to keep them, even if they are strangers, from being offended? Or would you hope they would be understanding, mature enough and respectful enough to understand you have different values and different personal definitions of what is and what isn't modest in regards to clothing?
There's a huge difference between a grown man staring inappropriately at a little girl and a teenage boy looking at what they would consider to be an attractive woman. Saying that you can't teach men or boys to not look inappropriately at females is mind blowing. Do we really think so little of males and do we all really believe they have no ability to control themselves? Sorry I don't buy it. If I were a male I'd honestly be very offended by this. As a female if I see a male who I find to be attractive walk by on the beach, attractive enough to get my attention, my basic thought is thank you sir may I have another? I'm not going to get up and follow them, I'm not going to cat call and make other suggestive noises, nor am I going to stare at them in a way that is inappropriate. The man could be with a shirt, without a shirt, in long swim trunks or speedos. Ok probably not speedos because I personally am not a fan, but that's just my personal feeling. I would expect my daughter once she's reached an age to notice such things to behave herself, the same way I would expect my son to have some self respect and not make a fool of himself. If he does then that's on him and not the woman he was looking at. It would then be up to me to again explain why he needs to behave better and very clearly explain my expectations of his behavior or we can leave. I wouldn't be leaving to shelter my teen from seeing body parts. I would be leaving because my teen obviously isn't mature enough to control their behavior in public. If they want to act like a toddler I will treat them like one and we will just go home until they can learn better.
I find it hard to understand how a woman who couldn't care less about men looking at her is the one in the wrong when it was the men you say were oogling her. Sounds to me like the men are the ones with the issue. Maybe if we all started expecting more out of our boys women wouldn't have to worry about being oogled? Maybe if people didn't make such a huge deal out of the human body more people could have a better time on vacation? Would people make excuses and blame a man if teenage girls were gawking at him for not having a shirt on and shorter swim trunks?