Fifteen year old Tiffany has the body and face of a twenty year old yet sucks her thumb like a baby. We've developed a close relationship and recently I made the decision to try to get her to stop. Today, I even broached the subject with her. (We discussed this in the hall between classes and it was a private discussion.)
I want to see my sweet (but difficult) little student grow and while I don't have a lot of confidence in being able to change this behavior, I am determined to give it a try. If I succeed great, if not, nothing will be lost.
Let's suppose I do help her to break this habit. I will have helped her pass on to another stage of her life and will have done something good for her. And, let's suppose, I can't get her to pass math, even if I spend many extra hours working with her. The value added data will not show me in a good light. The way we help them grow is something that cannot be measured in numbers.