Our chickens are 17+ weeks, and have NO interest in the nests - if I put them in there, they squawked and run out. Today, I was cleaning out part of the coop - we have doors at waste level, and they were open, the main rooster came in the coop, hopped into one of the nests and started making a sound like "pip pip pip". Curious, a bunch of the hens came in and watched him. Finally, one of them hopped in another nest. She didn't stay long, but wow, it was too funny to see the rooster showing them how to do it.