I’ve often heard people say that math is one of the few school subjects where marking isn’t subjective, but apparently not:
Beginning in 2002, the researchers studied three groups of Israeli students from sixth grade through the end of high school. The students were given two exams, one graded by outsiders who did not know their identities and another by teachers who knew their names.
In math, the girls outscored the boys in the exam graded anonymously, but the boys outscored the girls when graded by teachers who knew their names. The effect was not the same for tests on other subjects, like English and Hebrew. The researchers concluded that in math and science, the teachers overestimated the boys’ abilities and underestimated the girls’, and that this had long-term effects on students’ attitudes toward the subjects.
Full news article: “How Elementary School Teachers’ Biases Can Discourage Girls From Math and Science” C. Miller at NYTimes.com
Original research paper: “On The Origins of Gender Human Capital Gaps: Short and Long Term Consequences of Teachers’ Stereotypical Biases” by V. Lavy and E. Sand.