Trying out my technique on the boy again:

Me: “Tell me something happy that happened to you at school today.”

Boy (completely serious): “Ummm, being a Zen Buddhist.”

Me (trying to keep the smile out of my voice): “How do you be a Zen Buddhist?”

Boy: “Well, I try to be like Stillwater and am just very peaceful and quiet.”

 
 
 
*As a side note, I highly recommend all the Jon Muth books. “Zen Shorts” is a good place to start.  Great stories that introduce Zen principles and approaches to life problems in a way that kids understand, all illustrated with beautiful watercolor paintings.