Rosenthal, R., & Jacobson, L. (1966). Teachers' expectancies: Determinants of pupils' IQ gains. Psychological Reports, 19, 115-118.
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This study found out that teachers’ expectancy can be a significant determinant of students’ responses/behaviors. The names of experimental children were given to each teacher who was told that these students would show unusual intellectual gains according to intelligence test. However, the children have been randomly assigned to the experimental condition, therefore, the experimental treatment consisted of nothing more than being identified to their teachers as intelligent children. Eight months later, these experimental students showed significantly greater gains in I.Q. than did the control group. The study found out that the effects of teachers’ expectancies were greater for younger children.