Rooster or Hen

[Santa Fe Strong]

I picked 8 chick up on December 3 and I was told they were 3 weeks old. Supposed to be all hens but as they’ve gotten older two or three are starting to resemble roosters. One of them I’m almost positive it’s a roosters.
So I was supposed to get 4 Ameraucana and 4 New Hampshire Reds pullets.
Hampshire are all hens but the Ameraucanas are the ones I’m not sure about. Can anyone help me determine if they are hens or roosters?

 

[Mylied]

I've only seen that feather color with pullets, but someone else might know more than me.

 

[AmazingRachel]

I doubt that one could definitively tell at that age with the breeds. While you can get an idea by watching comb development (the combs that get bigger/redder first are usually males), a fail safe method is seeing if the saddle feathers at 3 months have pointed (male) or rounded (female) ends.

 

[Folly's place]

It's still early, but one of those chicks does have a larger comb. See in a few more weeks...
Mary