I would think there are more studies on young girls dressing like grown up sexual women.
But once again I think the results of any study would greatly vary depending on many factors.
But I still would not be in favor of the government passing laws on how people of any age must dress. Except what we've basically agreed on in this conversation total nudity and such in public. Umm. There are some marked beaches where nudity is okay. But these are things that would not apply to schools.
Once it starts on one group where does it stop?
No one can simply say it's human rights or children's rights to impose some dress code on a multi cultural world or population.
I recently had a conversation with a friend who had spent sometime in another country where formal dress is not dresses for women and suits for men. Well in the course of the conversation she says, "The women there are start to follow Biblical standards and wear dresses to meeting." Say what?
I asked her to show me in the Bible where it said to wear dresses to meeting. Well it doesn't. It says modest. It say well arranged. It talks about honourable occations. Her reply was you know what I mean. Well know I don't. I know the women where she was were pants and shear or lace type tunics with a cami under it. That has been their formal dress for irk 100's of years. So for them that is modest well arranged and good for an honourable occation. To expect them to embrace western dress while in their own country is wrong and a wrong mind set. Even if a person came from that country to mine it would be wrong to insist they observe the standard I'm accustom to.
Anyhow part of that conversation was that my friend thought the shear/lace tops was cami under was very sexy. Well knowing where she was the people there doubtless thought her knee length skirts were very sexy.
Individual humans need to figure out how they are going to interact in this world.
I posted the first part of this before I read your reply.
What evidence do you have that hijab real does prevent developement of fine or gross motor skills?
A few years back I saw some young girls in hijab at the iceskating rink. They were doing a dam good job at it. Better then the young lgirls with me who had never had a hijab on in their life.
Cognitive delays?
I've worked with a few nurses, radiographers, dietitians and other medical staff that wear hijab none seem delayed to me.
My sister (now retired) was a master teacher for students with special needs she never mentioned an especially high rate of problems among child who wore hijab. And yes there were children in here area who wore hijab.