Rick said a couple of things that reminded me of working with small children.

If an adult student has "stage fright" so bad that they cannot play the instrument in front of even their instructor...try playing in front of small children. They love you even when you make mistakes.

Also, Rick mentioned tuning the guitar to an open D...whatever that is ;-) A really neat idea for a children's program is to line up about 12 little folks each with their (Mom or Dad's) own guitar...tune each group of three or so to a different chord...and let them strum a song much like a bell choir, coming in on their chord. Warning though...you need some help with the logistics of all those little people and their parents' guitars!

Mary