When I was travelling earlier in the year I saw this poster on the back of an office door. I immediately recognised some great conversation starters for our family. These would work really well around the dinner table:
What was the best thing I heard today?
What was the best thing I saw today?
What was the best thing someone did for me today?
What was the best thing I did for someone else? (I personally prefer this to be less public discussion but it does give you opportunity to see into their world, and give praise but the balance is that God rewards those who do things in secret)
What can I do to improve tomorrow?