I've read that the chicks with a dark line down the tops of their heads are the females. Also, that the feathers on young chicks tend to be fuller on females and more sparse on males. Not really sure how accurate this is. I have noticed that some of my chicks are thinner and more upright and some are shorter and more "squat" for lack of better terms. I think they're about a week old. Can you tell sex by stature at this age? I've included a few pic of my babies if anyone wants to venture a guess as to what I've got. The guys at the feed store are kinda fond of me so I think they'll probably let me swap out the boys!
They didn't really wanna keep still so I'm sorry they kinda move from pic to pic. And pardon my terrible manicure! Lol