When you turn editing on (button at upper right of page) a number of icons may appear on the page. In the newer versions of Moodle, many of these icons can be found in a drop-down menu that appears when you click on the word "Edit." Here are some of the icons that allow you to make the changes in resources and activities:
The "Move" 
image appears in many places in the newer versions of Moodle in many different places. When you put your mouse over this icon you can then click and drag the item to various locations on the page. Older versions of Moodle use the second "Move" icon, described below.
This second "Move" icon usually appears only in prior versions of Moodle. It allows you to move material from one location to another. After you click on this icon the associated material will disappear from the page and a number of small boxes will appear throughout the page. If you click on one of these boxes, the material will reappear at this location. In newer versions of Moodle the first "Move" icon (described above) is the one that usually appears.
These are the Edit title, Move Right, Move, Update, Duplicate, Delete, Hide, and Assign roles icons respectively.
This is what happens when you click on one of these icons (going from left to right):
"Edit title" allows you to change the title displayed.
The "Move right" icon will move the associated material to the right. After this happens, another icon will appear allowing you to move it to the left. You can move right or left to the edge of the page. This is useful for formatting and organizing your page.
When you click on the "Update" icon, the window will change and you may then edit or change the associated material. Thus, this is a very useful icon for you to use to edit material and settings throughout the site.
"Duplicate" allows you to duplicate the activity or resource. You can then move, edit, or otherwise change the duplicate.
When you click on the "Delete" icon, a different window appears asking you if you really want to delete the associated material. If you click "Yes" the associated material is deleted.
When you click on the "Hide" icon, the little "eye" will close and go to sleep. The associated material will become gray. This material is now hidden from student view but you can see it. The icon itself changes shape to indicate a closed "eye" and is now the "Show" icon. If you click on this icon, the material can now be seen by students and is no longer gray. Thus, this a hide/show toggle.
"Assign roles" allows you to control which groups can access or use a resource or activity if you have put students in you rcourse into groups. There is also another icon that allows you to change permissions on a resource or activity. If you have questions about this, please contact the Moodle administrator.
There is another very useful icon that appears throughout the site, the "Help" icon. 
Whenever you click on this icon, a new window pops up displaying help that is specific to the choices that were listed near the "Help" icon itself.