To switch rooms from anywhere in Socrative, click on the room name from the main header and select a new one from the drop-down list.
You can keep rooms from appearing in the list by clicking on Rooms, and unchecking them in the In Menu column.
You can also switch rooms by clicking on a different room in the list. The room that is currently active will appear bolded in black, while inactive rooms show as blue.
If you have an activity running in any of the rooms, the status icon will appear animated. If you are done with an activity, you can finish the quiz from the results page.