Are these roos or hens?

[Shore]

I adopted these from a 2nd grade teacher who hatched them with her students. Hatched May 1, now 17 weeks. I have 4 and they all look basically the same (here are 3 of the 4). I'm a new chicken owner & didn't think about the possibility that they might all be roos! Heard crowing and can't have roosters in the neighborhood. Can anyone help ID? Thank you!

 

[Gray Farms]

These three are all Buff Orpington cockerels.

 

[Cel45]

X2

 

[donrae]

Handsome boys.

 

[drumstick diva]

YES

 

[austrolover1]

Cockerels.