Do expectations really make a difference? Robert Rosenthal, the first psychologist to systematically study this with teachers and children, found there were IQ gains in students in whom they expected this outcome. In addition, as noted on NPR.com:

“As Rosenthal did more research, he found that expectations effect teachers’ moment-to-moment interactions with the children they teach in a thousand almost invisible ways. Teachers give the students that they expect to succeed more time to…