As a group list some of the most "unwise" things you've seen someone do.
Read Proverbs 15:31. As a group, come up with some examples of a "life-giving" rebuke.
Read Proverbs 18:15. As a group, create a definition of "discernment".
Every time you hear, see, read (etc.) something, you have to sort it through a set of criteria in your mind to determine whether or not it is true and good. Sometimes, things are obvious, but sometimes they are not so clear. Discernment becomes important when you are trying to decide whether or not to believe those things you have heard.
List four criteria you might use to determine the value of an idea or statement.
Read Proverbs 19:20. How does this passage tie together the other passages you've read during this time.
Spend some time talking times you have been given wise advice or instruction. Tell the group whether or not you followed it, and what the result is. Talk about the current issues in your life where you need some discernment.
Encourage and pray with one another.