Example: step 3

On the class timetable, click several times on <Other element in period> until the room details are displayed (or you open the timetable Class schedule big which already displays the rooms).

Repeat the same process for the room timetable until each period displays the class scheduled to have lessons in the room (or you open the timetable Room schedule big .

Just have a look at the timetable of a class and of its home room. The examples above show class 1a and its home room R1a. As you can see, the class is not always scheduled to have lessons in its home room, because the room is occasionally occupied by other classes