Pullers or cockerels

[Crazy for Chickens!]

Your Red Sex Links are pullets. The cockerels are white with red shoulders.

Your others are too young. Post pics of their combs in 2-3 weeks.

 

[Coraline_abel]

Some updated pics of the chicks

 

[Crazy for Chickens!]

The BR is most likely a Cockerel, seeing the red wattles. Maybe post back in a week to be sure.
I can't see the comb on the second bird.

 

[Mosey2003]

Barred Rock is still a pullet.

 

[alexa009]

All of the chicks are too young to be sure. Nothing really indicates their gender at this age. The Red Sex Link is the only one that is definitely a pullet since males only appear to be white.