I've noticed that people, as working adults, are rarely interested in hearing about professional accomplishments in social settings in the same way that they tend to be interested in hearing about a student's classes. So, unless someone asks me directly, I try to avoid talking about work. I'm not trying to be cagey; I just figure if they're interested, they'll ask.
For me, whether work is going well, poorly, or unremarkably, there's little to gain by sharing unprompted. If things are going well, comments can easily be mistaken for arrogance or bragging. If things are going poorly, stories can be confused for complaining or whining. And if things are going unremarkably, then people are going to get bored, but may be too polite to interrupt.
Life isn't just about work. There are plenty of other interesting things to talk about.