Last year I had a student (let's call him Dave) who was a real problem kid--disinterested, often absent, just barely scraped by to graduate. Today, out of the blue, I got this note from his mother: "Dear Mrs. K., Thank you for your impact on Dave's life. It isn't reflected in his grades or writing skills. It's reflected in the stories he tells of his time in your class. You made a difference!" Made me teary.