Every one that has long, narrow saddle feathers with pointy ends is a cockerel. (The saddle feathers grow on the back, in front of the tail, and hang down on both sides of the tail.) Cockerels also grow feathers like that in their hackles (around the base of the neck.)
I am pretty sure I see male saddle & hackle feathers on every chicken in your most recent photos.
A female chicken NEVER has that kind of long, narrow, pointy saddle and hackle feathers unless she has a major hormone problem (which is rare, prevents her from laying eggs, and can cause her to act like a rooster as well as looking like one.)
Also, all the chickens in your recent photos have combs & wattles that are the same color and similar in size. That means they are all the same gender as each other. Since some are crowing, that gender is male. If there was a female, her comb and wattles would be much smaller and more pale in color. By this age, the difference would be very obvious.
Of course you can keep them as long as you want, but I am very confident they are all males. (I know it's much easier to be sure of gender when you have both males and females, because that makes the differences so much more obvious. I regularly have trouble sexing chicks if they are all one gender, but not when there are some of each.)
I was thinking the same, they must all be the same gender. This was what made me question the chances of them being all male, but judging my their feathers and the fact 2 can crow, they must be all males. What are the chances!
