You can also manually archive the study. Set the end of the term in the past and click "Save". An extra button "Archive" will appear. Click to manually archive the study. After three months of inactivity the survey will automatically be moved to the archive.
Retrieve surveys from the archive
When the survey is archived you can retrieve the survey including it's results by clicking under "Actions". If you only need the questions and not the data, you can copy the survey by using the button on the right hand side of the screen.
Do you want to avoid the auto-archive option? Go to the the menu "Survey" and "Settings". You can select the "Block automatic archiving" there.