How do you tell the difference between hen and rooster when they're chicks or older.

[Run Amock DucksNChickens]

Rose looks like the only potential pullet to me... None are pure Araucana. Louie looks to be the only one with some potential Araucana blood due to having a pea comb (assuming all are f1 mixes)

The eggs came from Araucana hens and rooster. I was told they were purebred.

 

[Run Amock DucksNChickens]

Louise and Rose are Pullets. The other 5 are Cocks. Thank you for your input. I've got another 11 in the brooder that look mainly female.

 

[The Moonshiner]

Feather sexing is 'only' accurate if they have specifically been bred for it. With those bred for it, all the girls will have two fast feather genes and the effect is multiplied and since boys can only hold 1, they feather in slower. Without this specific breeding, the girls could have any combination of fast feathering genes and may be just as slow as the boys.

This isn't correct.
Females only get one gene and it comes from their father.
Males get two genes. One from each parent.
It needs to a fast feathering male bred to a slow feathering female.
The daughters get a fast feathering gene from the rooster and feather fast.
The sons get a fast feathering gene from the rooster and a slow feathering gene from the hen.
Slow feathering is dominate over fast feathering so they feather in slow.