From the ArcaMax Publishing, ArcaMax Publishing Newsletter:
http://www.arcamax.com/news/arcapub/s-565991-908483
Finding one of her students making faces at others on the playground,
Ms.Smith stopped to gently reprove the child. Smiling sweetly, the
Sunday School teacher said, "Johnny, when I was a child, I was told if
that I made ugly faces, it would freeze and I would stay like that."
Johnny looked up and replied, "Well, Ms Smith, you can't say you
weren't warned."