Power of Positive Beliefs

I am an educator as well as a coach and am interested in what it is that brings out the best in the people with whom I work. Over the last few years I have read a great deal of research on the power of beliefs. I am convinced that it is essential that I hold, and communicate to my students or clients that I believe in their ability to learn, to heal, and to grow.
We have to hold and project these beliefs even when, or perhaps, especially when the person we are working with does not hold them. In a recent study, it was found that teenagers from economically disadvantaged families were more likely to attend college if their parents, especially their mothers, were optimistic about the teens chances of enrolling in college.
I read once about a teacher who was given a list of student names with numbers ranging from 125 to180 after their names at the beginning of the school year. Believing that she had been given a class of gifted students, she worked hard all year to provide opportunities for these students to do well. At the end of the year, she asked for another class of gifted students since they had all performed outstandingly. She was told that the numbers were their locker numbers, not their IQs.