Add detail to how we use google maps.

index.html

@@ -121,7 +121,13 @@
         <li><a href="https://www.youtube.com/user/destinws2">Smarter Every Day</a></li>
     </ul></li>
 
-    <li>Geography: <a href="https://maps.google.com">Google Maps / Earth</a></li>
+    <li>Geography: <a href="https://maps.google.com">Google Maps / Earth</a>
+      <br/>
+      <i>Click the sattelite view, and then the small globe icon on the bottom right. Zoom in to
+      different places, ctrl-drag to get a 3d view (sometimes), zoom out / pan to travel to other
+      significant places. Zoom all the way in to get to street view. Zoom all the way out to see the
+      earth, the international space station, and other planets.</i>
+    </li>
 
     <li>PE:<ul>
         <li>Parkour<ul>