Study: Teachers overestimate boys in math and girls in languages. Teachers tend to judge girls' language skills and boys' math skills better than the children's actual performance on tests.
Distortions in the assessment of primary school children were systematically related to the gender of the students. The distortion in the area of mathematics is greatest in Germany, but in the areas of language and math it is in England. In the USA the differences were much smaller. The study was published in the journal “Social Science Research”