We have a pretty large coop. I hatched a couple eggs last spring, and when it was time to move the chicks out to the coop, I put a large door crate in the corner. I kept them locked in it for a couple weeks. Then, I'd let them out a bit while I was working around the coop. Then, I'd wire the door open enough for them to get in and out, but too narrow for the adults to get in, so the chicks could escape if need be. Then, eventually, I removed the crate. One bird turned out to be a roo, so he went into the soup pot last fall. The other is a hen who is just another member of the flock.