All You Have To Do Is Ask
One student who has a keen interest in beekeeping was excited to have talked with an Amish beekeeper at a farmers market. Another student attended a Bible conference where they met total strangers with similar interests.
One student did not have a great weekend because mom was sick and needed to help out around the house. And another student and I are reading the same trilogy and we were able to discuss the same chapters.
Later, a student asked if my question had anything to do with class. I honestly replied that it did not, that I was only taking an interest in their life. A teacher can learn a lot about students through a few simple questions and by taking the time to listen to what's important to them.