ANSWER:

It is not permissible to enter a “real” masjid for a menstruating woman, even if it’s for attending classes. If this is not a “real” masjid and it is only a prayer hall which can be changed anytime by the administration into a class or a meeting hall, in this case, a woman in her menses can enter it.

2nd floor of our local mosque is for women.There are few rooms on that floor.The big one is for prayer & rest are used as classrooms for women & kids.Can a menstruating woman enter in one of those classes to attend class or exam.Ensuring she will not go to the prayer room.Even she won’t have to cross any prayer place to reach that room.She will have to use the stairs.