Hi all,
I teach once a week at a drug rehab for teen boys. They only had one guitar, and I previously could only teach one at a time. Now they have five guitars.

I am looking for your suggestions for teaching five at once. Most of them have never picked up a guitar before. My goal is to teach something really simple that we can all play together at the end of the hour. (I could sing) So... perhaps a song? What would you choose?

Thanks everyone, for any suggestions.