If you accidentally deleted an activity or resource on your course page, you can retrieve it through the Recycle Bin, which is within the Administration tab to the left of your screen.
Please note you can only retrieve resources and activiites on your course page. In the current version of Moodle, resources and items within activities (for example, pages in Books or Lessons) or pages in your course do not go into the Recycle Bin in Wattle and cannot be retrieved.
You will be taken to a new screen which is the Recycle Bin. (Be aware that when you delete an item, it may take up to 5 or more minutes for the item to appear in the recycle bin).
There are two items in the bin shown in the image. You can see there is an option to restore, or delete. If you delete the item from the Recycle Bin, this is a permanent deletion and the item will not be able to be restored. To restore, click on the "restore" icon adjacent to the item, and it will be returned to its original place in your course.
As you can see, there is a notice to tell you that contents in the Recycle Bin will be permanently deleted after 7 days.
In the recycle bin there is also an option to "delete all" of the items listed. This is useful if you are doing mulitple deletions and wish them to be permanently deleted.