You can export a copy of your student roster for your room if you'd like to keep a backup.
Click on Rooms, then,
Find the room for which you'd like to download the roster, then click on the Roster icon
A menu will appear that shows the format of the file. You can click Change to adjust the column order or the file type (.csv or .xlsx). Click Export if you're happy with the settings.
Whether you're trying to add or edit a roster, if you have an activity running in the room, you won't be able to open the roster menu. You'll see the error message below:
To finish an activity, go to the Results tab in your account and click the Finish button. Check out this guide to help you on how to end an activity.