I finally got around to adding a chicken door to our coop Sunday evening. Through out the summer we just left the larger door meant for maintenance access open. The downside to the larger door being left open was rain/snow could blow into the coop. Anyway, I put in the door and added a ramp. On Monday and again yesterday 4 of our hens went under the coop rather than in it - yesterday our Speckled Sussex was actually on top of the 6ft fence just next to the coop.
How do I get theses hens to use the chicken door? We have been shooing them out from under the coop, picking them up and placing them in the chicken door hoping they would realize that is their way back in. I am just not certain this approach is working. More worrying, the water and food is in the coop now to keep it from getting rained/snowed on. I have a water in the run, but it is not heated and freezes on me.
It's been a while, but I think I may have had a similar issue. (Now the newbies learn by watching the mature ones, so no teaching required.) I probably trained them with treats. Place some mealworms up the ramp & by the door area. I remember training them to come inside the coop when called. (I'd stand inside & call them while shaking the treat can. They'll come running from anywhere when they hear that sound!)