Female teachers have been identified as a key reason why boys are behind in the classroom.
Research, carried out by the London School of Economics, found that boys will lower their expectations if they think their work is going to be marked by a woman because they believe their results will be worse.
Their suspicions proved correct as female teachers,on average, awarded lower marks to boys than unidentified external examiners, while male teachers awarded boys higher marks than external examiners.
The findings could have immense repercussions for Kiwi boys due to a lack of male teachers in the New Zealand education system.
Professor Alan Smithers, a leading academic researcher, called the findings "fascinating"..
The research was carried out among 1200 children in 29 British schools.
It also revealed that girls tried harder if they had a male teacher because they believed they would get better marks.
Their suspicions, however, proved wrong as male teachers tended to give them exactly the same marks as the external examiners.
The study showed that boys believed their answers would be three per cent lower if marked by a woman. The girls thought their results would be six per cent higher if marked by a man.
Mr Smithers said the study stressed the importance of independent marking for examinations and assessments..