What sort of entrance/exit do you have - is it a ramp or a "jump down/up"?
Do they know to come when called? This is an easy thing to teach by associating your call of something like "Here chick, chick, chick" with the arrival of a favorite treat - you go outside of the coop and call, they come out to get the treat - repeat in reverse to get them back into the coop.....or you can even do a "trail" of the treat leading out of the coop/down the ramp and then repeat in reverse.
Right now it is a small jump down ... eventually there will be a ramp but not a big one ... We just got them Saturday so they do not know to come to treats yet ... but I figured they are probably stressed right now with the "move" to our house, new coop, etc. I am just thankful that they have each other thru all this ... at least they have "someone" familiar with them while going thru all these stressful things