The black one and the Brahma are pullets. The one in the leftmost photo and the one in the middle of the second photo (I think it is the same bird in both pictures) is looking like a cockerel to me, going by comb. It may just be a light shade of blue or it may be blue splash. That's a close call.
I think the blue Ameraucana is the only suspicious one. Clearer photos of its comb would help. Its coloring is patchy like a male's but that could be because it is blue splash rather than straight blue.