You can teach an old hen new tricks. Watch Luna "pecking out" the Queen of Spades from a deck of cards.
It's quite amazing, isn't it? Chickens are smarter than we think. They recognize shapes and patterns, and have a very good memory. I taught Luna this trick using positive reinforcement training, which consists of rewarding wanted behaviors and ignoring the unwanted ones. It took her only 10 sessions of about 7 minutes each. Here are videos of each training session: https://www.youtube.com/playlist?list=PLbmXHhMcpoGdA-J92f9IfS2eu66Gs4rtt