SwimOffice Admin - Webmaster Event Admin 
  1. To Automatically Archive News  - when you create a news item you can select a date for the news to automatically move to archive. Select Add New > News Expiration Date and enter in a date & time (remember to use a leading zero for times such as 07:00pm)
  2. To Manually Archive New - Select your news items and the 'Archive Selected' button to move to the archived tab

See Also
Create a News Item
Limiting the number of news items on your home page