I dont know abt the foreign universities but specially in Pakistan ,U just check out the behaviour of som male teachers with boyz and gals , they are soo polite and soft with their female students just lik the way(Such a helping attitude u cant even imagine ) …now when its Guyz turn to talk or discuss som prob/assign/anything ,Check out the sudden change in their freq and accent and behavior.I think boys are paying the sam as gals are paying:hehe:.U can find out a great marginal difference in marks as well just because of this biasing .I m always against such biasing and dislik such kind of facility members .This kind of biasing must be discouraged. 
i know these kind of faculity members are young and immature as well.A mature faculity members avoid to do this kind of blunders.THEY just consider all students just lik their own kinds.i know som1 ppl didnt agree with me but this is reality .
the Group members who are facing the sam kind of prob just share.. 