A couple of years ago, my 80-year-old father saw me hand-feeding chickadees and nuthatches at my house, and acted more interested in birds than I had seen before, so I gave him one of my field guides. He started watching birds with his cheap binoculars, and called me every time he got stuck on an ID. My brother and I got together and bought him a very high-quality monocular for father's day, and he's still at it. His field guide is loaded with little scraps of paper with dates, etc - he refuses to write in it though I urge him to. And he still calls me when he stuck trying to ID a bird. Some people are eager to learn at any age.