Are they hatchery birds or is there a chance they're mixed breeds? I'm thinking mix on a few of them....
first bird looks like a mix. Feathered legs and straight comb could be Cochin, but the white skin is probably Orpington or Sussex. With that coloring, I'd guess Orp.
need a better pic of the black bird. Does she have a beard? And what do her legs look like?
third is a mixed breed pullet, probably with light Sussex background.
fourth, not sure if that's a pea or straight comb? It looks like it could be a pure bred bird from the leg feathering, but the color doesn't match anything I'm aware of on this side of the pond.
fifth could be a buff Orpington, but is that black ticking around the neck? If so, probably a mixed breed.
last bird is a cockerel if the same age as the others. With the white skin, I'm again thinking Sussex background. The barring could come from a barred Rock, most likely.