3. What is GPS?  A GPS (Global Positioning System) is a handheld device that can determine your approximate location almost anywhere on the planet.

4. What is GPS?  A GPS unit uses 24 satellites placed in orbit by the department of defense to calculate your position.  With the use of at least three satellites a GPS can triangulate your exact longitude and latitude coordinates.

5. What is GPS?  Since a GPS unit knows your location it can also determine your speed, distance traveled, direction, and even elevation.  A GPS unit can also be used to navigate from one location to another.

6. What is GPS?  Some GPS units come with added features such as base maps, electronic compasses, lunar charts, and even voice navigation.

7. How Does GPS Work?  Let’s say you don’t know where you are but a passerby tells you that you’re 238 miles from Cleveland.  That puts you anywhere on the perimeter of a circle around Cleveland!

8. How Does GPS Work?  Another passerby stops and tells you you’re 340 miles from Boston.  So not only are you on the perimeter of the circle around Cleveland, but around Boston too.  There are now only two possible locations!

9. How Does GPS Work?  Finally, someone stops and tells you that you’re 272 miles from Baltimore.  You now know right where you are!

10. Basic GPS Functions The Power Button Press the power button and hold for 1 second to turn it on. Press again to turn the backlight on Press again to turn the backlight off Press and hold to turn the unit off

11. Basic GPS Features The Satellite Page After powering it up, the unit will attempt to ‘lock’ onto the satellites. You must be outdoors with a clear view of the sky to get a signal. Once locked on, you’re ready to navigate!

12. Basic GPS Features The Compass / Pointer Page The GPS unit now displays the basic Pointer Page This page is used to navigate to the chosen waypoint by following the pointer arrow.

13. What is Geocaching?  Geocaching is an entertaining outdoor adventure game for GPS users of all ages.  The basic idea is to set up caches (hidden prizes) all over the world and share the locations (Latitude / Longitude) of these caches on the internet.

14. What is Geocaching? Using the Geocaching Website, www.geocaching.com, you can search for caches by: By Postal Code By Coordinate By State/Country By Keyword By Username (Found)/(Hidden) By Waypoint Name, and By Address (US Only)

15. What is Geocaching?  GPS users can then use the coordinates to find the caches.  Once found, the visitor may take something from the cache, leave something, and/or sign the logbook.  The ‘find’ is then logged onto the Internet website where statistics about found and hidden caches are maintained.

16. Geocaching in the Classroom  Scavenger Hunt- Students use longitude and latitude coordinates to find hidden items around the school campus.  Content Specific Caches- Hide caches around the school campus and inside each cache have a problem or question about a specific subject.

17. Geocaching in the Classroom  Science Cache- Each cache is actually a tree, plant, rock or other object that students must identify.

18. What is a Travel Bug?  A travel bug is a trackable tag attached to an item chosen by its owner.  Each travel bug has a unique tracking number stamped on it.  The travel bug becomes a hitchhiker that is carried from cache to cache and its progress can be followed online.

19. Travel Bugs in the Classroom  Travel Bug Race- Communicate with another teacher in a different state and release classroom travel bugs to see which travel bug can reach the other school first.  Travel Bug History- Release a travel bug and have students research the history of each area that the travel bug stops.

20. Travel Bugs in the Classroom  Travel Bug Science- Release a travel bug and have students research the type of biome that the travel bug is in.  Travel Bug Language Arts- Release a travel bug and have students write a creative story about the travel bug’s adventures.

21.  Much of the information and many of the images were used with the permission of Michael A. Gallagher.