An Idea

Ten-year-old Daphne brought her report card home from school. Her marks were good...mostly A's and a couple of B's.

 However, her teacher had written across the bottom: "Daphne is a smart little girl, but she has one fault. She talks too much in school.
I have an idea I am going to try, which I think may break her of the habit."

Daphne's dad signed her report card, putting a note on the back: "Please let me know if your idea works on Sally because I would like to try it out on her mother."