Your expectations as teachers about your students can influence the learning performance of those students, both positively and negatively. In studies where teachers were made aware of the influence of their own expectations or where they had to explicitly express high expectations, this resulted in better learning performance of students. It is therefore advisable to express realistic and clear expectations to your students. The finding that your expectations as a teacher about your students can influence the learning performance of those students is known as the Pygmalion effect, the teacher expectancy effect, or the Rosenthal effect. This effect is explained by the fact that your attitudes and expectations influence your behavior, and that behavior is then interpreted by students. Students may feel stupid, for example, if you start sighing out loud after explaining something a second time, perhaps unintentionally. Unwanted expectations from teachers are usually based on stereotypical characteristics of the group to which students (seem to) belong, due to their ethnicity, gender, or socioeconomic status (SES). For example, it appears that teachers often view the future of students with a low SES more pessimistically than that of students with a high SES. The danger of (too) low expectations is that teachers (unconsciously) invest less energy in these students or express expectations that undermine the students' self-esteem.
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