Male ustaadhs are not supposed to be joking around with female students, asking them personal questions even if there is a curtain separating them.

Answer

It is haraam for male teachers to teach females even if there is a separating screen. The screen does not prevent them from amorous and immoral conduct with the girls. Practical experience has proven that these male ustaadhs are under the influence of their bestial nafs when they teach girls. Their mental equilibrium is deranged by lust. It is haraam for them to ask the girls even questions on Salaat and Qur'aan. It is haraam for them to listen to them speak. The voices of the girls are aurah. It is haraam, especially in this day, for males to teach girls regardless of the mock screen. The screen today in girls madrasahs where male ustaadhs teach them is shaitaan's trick to bamboozle the ignorant ones. It is only a flimsy cover which does not prevent the lustful conversations out of which develop even relationships between girls and their male teachers.