Key reason for gender gap - Female teachers give boys lower marks, study finds

The study was published by the Centre for Economic Performance, full paper (pdf). Article here. Excerpt:

'Ground-breaking research shows that boys lower their sights if they think their work is going to be marked by a woman because they believe their results will be worse.

It also shows their suspicions are correct – female teachers did, on average, award lower marks to boys than unidentified external examiners. Male teachers, by contrast, awarded them higher marks than external examiners.

The findings, published by the Centre for Economic Performance today, could have immense repercussions for boys because of the dearth of male teachers in the profession. Only 15 per cent of primary school staff are men.
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He said the research, carried out among 1,200 children in 29 schools across the country, had shown a possible reason for the glaring gap in performance between girls and boys right through schooling.
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Professor Smithers said: "It is fascinating research. It does stress the importance of independent marking for high-status examinations."'