Bible study book today is Matthew chapter 7 and verses 1-3 should be good to start off tonights group:
Do not judge others, and you will not be judged. For you will be treated as you treat others. The standard you use in judging is the standard by which you will be judged.
And why worry about a speck in your friend's eye when you have a log in your own?
Great book chapter that can fit into any day to day activity.