A brief tutorial on adding placemarks to Google Earth is available at http://www.googletouring.com/create.php

Students might not initially see the ways in which placemark symbols can be changed This is useful as you can use one sort of placemark to mark say chapters and others to mark plot locations etc. When editing a placemark, click on the picture next to the Name , and a range of other icons will appear. You can also change colour etc of placemarks – this is reasonably obvious.