If you're a female science teacher, male students tend to underrate you. Even worse, if you are a female science teacher in physics, both male and female students underrate you, according to a study of 18,000 biology, chemistry and physics students.Are female science teachers just worse than males and instead got the jobs because of social engineering? No, male and female teachers are equally effective at preparing their students for college, say researchers at Clemson University, the University of Virginia and Harvard University, it's instead gender bias. Their findings appear in Science Education online in the research paper, "Unraveling Bias from Student Evaluations of their High School Science Teachers."