Educational Expectations and the Pygmalion Effect

I'd heard the idea, but never under this name:

The Pygmalion effect, or Rosenthal effect, refers to the phenomenon in which the greater the expectation placed upon people, often children or students and employees, the better they perform.

Here's the experiment:

In the famous Oak School experiment, teachers were led to believe that certain students selected at random were likely to be showing signs of a spurt in intellectual growth and development. At the end of the year, the students of whom the teachers had these expectations showed significantly greater gains in intellectual growth than did those in the control group.

Or to put it another way:

"Whether you think you can or whether you think you can't, you're right." -Henry Ford