PROPER WAY TO COMPLAIN

A few weeks ago my purpose was to get our teen Sunday school class to "stop grumbling like the Israelites".  Before our class began, thinking I could get them into a different frame of mind, I asked them to share with the class "just one good thing that happened to them that week." Just one.
The first person said, "Nothin." Hmmm
I said to her, "I forgot, your parents lost their jobs, you were evicted from your home and you had nothing to eat this week."
She sat up in the chair, "what are you talking about? My parents are working, we had lots to eat, even pizza one night, and we're still living in our home." 
"Well, I guess you do have something to be thankful for then, right?"
I decided to do an experiment on my own. I went to Facebook, and checked what some of their friends were saying. I also reminded them I would be checking from time to time what they say on Facebook. A few of them slid further in their seats.
I couldn't believe some of the comments I read. One said, "it just keeps getting more complicated, or nothing good ever happens in my life, I have nothing to look forward to."
I reminded our class the Israelites grumbled for forty years, when it should have only taken eleven days in the wilderness.
Deuteronomy 8:2 And you shall remember that the Lord your God led you all the way these forty years in the wilderness, to humble you and test you, to know what was in your heart, whether you would keep His commandments or not.
I found a picture to share with them about complaining about their jobs. First, they should be thankful in this economy that they even have a job, and secondly I don't think any of them has a job like this one.