"Yes Johnny?" I tried to mask my surprise at his enthusiasm for this delightful topic.
"A diphthong is when you have a big ol' bowl of dip, and you dip your chip in the dip, and when you pull your chip out, there's a thong hanging from it," he gleefully announced.
Mmmmm. Forget cheese balls. The diphthong will undoubtedly be the favorite at any party.
After a good inner chuckle, I steered the discussion back toward phonics. I have to give little Johnny credit though; it turned out to be a pretty fun lesson. :)