Teaching Ideas for GPS


All the activities assume the use of a Garmin Etrex or Geko 201 type unit which can be connected to a PC running Easy GPS The graphics in the following section are based on the Garmin Geko screens

Getting to know your GPS

Bluetooth GPS units attached to a phone or computer are utterly simple, with no buttons at all. In most scenarios the GPS position data will be collected and managed via the interface of the program, which is likely to be fairly self explanatory. For example when using Phone2GEarth, the only options are to start and stop the data capture, and add a new placemark. Memory Map and Anquet map software running on a PDA or PC also allow you to capture waypoints.
In most cases students will be using handheld GPS units. Even the simplest of these are not very intuitive, offering a number of different features and screen views which can be confusing to the uninitiated. Sufficient time needs to be allowed for students to become familiar with a hand held unit before attempting a crucial piece of fieldwork! As I mentioned on my GPS for teachers page, I recommend the Garmin Geko 201 unit for children and I have prepared a simple Users Guide. It's designed to be printed off in colour and then laminated back to back.

user guide
Download the guide
(0.9 mb Word doc)

Garmin have a good introduction to GPS for beginners to download as a .pdf file (524k) which could be modified slightly for students.


Getting Started

How does GPS work?
gps  page satellite
A good initial activity is to turn the handheld unit on and get students to observe the initial page which shows the unit acquiring a satellite.
The Trimble web site has animations that explain what is going on, however this presentation rapidly gets complicated.
I recommend a brilliant little interactive application at UK Telematics online (scroll down to Application Downloads), which explains the basics in a few easy steps.





What is a waypoint?
gps waypoint
The next stage might be to get students to learn the basics of creating a waypoint (or GPS location) On the Geko 201 this is just a matter of pressing the OK button for a couple of seconds. It is good to show students how to edit the names of waypoints.
The process of downloading the waypoint to Memory Map, or to Easy GPS and then Google Earth or Google Map via GPS Visualizer could be demonstrated.



What is a track?

gps map Once the basics of waypoints have been understood, the next stage is to get students to observe the electronic 'breadcrumb trail' that is left behind as you walk. This is the track. and is visible on the map page of the Geko 201. Students should be shown how to clear the track log and save and name new tracks.
The track can be used to retrace your route while outside, and it can also be uploaded to a map or Google Earth to see where you have been.
Individual tracks can be saved and named for use in various projects.


A fun activity is GPS drawing, where you have to create words or pictures using a GPS track. If they are large enough the results can be seen in Google Earth. I really like the idea of virtual graffiti and students could be challenged to see what they can come up with. A challenge is that words have to be in joined-up writing, unless you overlay several tracks on top of each other. I have written a short article about this here. The GPS Drawing web site is a useful resource.

What information can be recorded with a GPS?
gps trip computer page
Students should be shown how the unit monitors their speed, elevation and other variables The trip computer page illustrates a number of data fields that can be displayed on the screen.
A good activity would be to get students to reset the trip computer and then compete with each other over 5 minutes to see who can record the fastest speed or travel the furthest distance. A more sedate activity would be to find the highest elevation in the school grounds.
This would be a good time to try some of the games like "Geko Smak" that come with the Geko 201 unit.



Geocaching

This is a well established activity that combines elements of orienteering and treasure hunting. Geocaches themselves take many forms, most often a small box with some objects and a book for recording visits. A simple geocaching course can easily be created within a school's grounds. To do this, walk around the proposed course fixing waypoints as you go. You might include some hidden objects, a series of numbers or letters, or questions for students to answer. Once the waypoints have been collected, download them to a PC using Easy GPS. Then clear the waypoints from the student's handsets and upload the waypoints to each one. You might change the waypoint numbers to ensure that they don't all chase the same waypoint at the same time. This activity will teach them the basics of GPS navigation.

More information about geocaching on the official geocaching web site.


Athletics performance

track map
This activity would make a great collaboration with the PE department. The GPS units can be used to monitor individual performance on the cross country route. Clear the track log and then get student to run. Their performance can be analysed in Magnalox or GPS Visualizer afterwards. The tracks reveal at which point students are running faster or slower, and this can be compared with elevation data for example. In the example above, the track has been coloured to show speed.
Students could plan their own cross country course. I notice that Magnalox doesn't reproduce an oval running track very well - an example is here, compared with the same track in GPS Visualizer.


Mapping projects

map points
Students should be able to prepare excellent maps of point data for their local neighbourhoods. A simple project might be to map trees, potholes, post boxes or telephone booths. Simply upload the waypoints that mark the information to GPS Visualizer. Different colour pins can be chosen. This example shows how waypoints can look when the output is a Google Map.


Other ideas for mapping:

It is easy to create simple maps from GPS tracks - the basis of the Open Street Map project.

contour map
Although the standard GPS elevation is rather unreliable, it could be possible to get students to make contour maps from tracks. The procedure would involve walking up a hill, while observing the elevation readout, and stopping at the desired height intervals. Clear the track log and then walk across the hill slope, keeping an eye on the elevation readout to record a track for each height interval. Save each completed track with a number corresponding to the height. I should admit that this is quite a time consuming exercise and is probably not an activity that I'd do with students! Here is an example of a simple contour map. GPS Visualizer has been instructed to colourize the tracks according to their elevation. (Note that this only works in Firefox)

Download the original .gpx data I used for the above demonstrations

Surveying

GPS units can be extremely helpful for surveying tasks, for example sand dune profiling. It really helps to have a unit with a proper barometric altimeter which will give much better results than the GPS elevation. Magnalox provides an excellent way to display the results and photographs can be included in the profile which is highly interactive. I described sand dune surveying with GPS and Magnalox in this article. See an example sand dune transect on Magnalox. (Note that the information can be displayed on a Google Map or Google Earth as well.)

Other ideas in brief

Here are some suggestions for using GPS within Geography / ICT teaching and outdoor education.

Return to exactly the same fieldwork site each year - especially important for fluvial or coastal studies where data is collected over the long term.

Systematically sample along a transect. Some software/hardware combinations such as an Etrex and PDA with Memory Map will allow you to set proximity alerts that remind you when you have entered or left an area; useful for large scale urban transects.

Some digital maps like Anquet and Memory Map allow the creation of hotspots that open a file, for example a picture, sound, text or spreadsheet resulting in an interactive map. Mark the hotspots in the field using a GPS.

View a moving OS map or aerial photo of your fieldwork location. Are you in the middle of a bronze age settlement on Dartmoor? What is that quarry like behind the keep out sign? And most intriguingly of all, why is that MOD installation in front of my face not marked on my map? Some software such as Oziexplorer allows you to work on a real-time moving scanned map on your PDA or laptop.

Work out transport times / distances during urban fieldwork. For example compare the average speed of bus, car, bike and walking. Has the London Red Route scheme improved journey times? (I don't know because I wasn't out with my GPS before the introduction of the scheme!)

Create GPS routes of your local area with an accompanying leaflet and distribute them in the local tourist office. How about an making an off road cycle guide? - Etrex and Geko units are excellent for mountain biking, you can attach them to your handlebars and virtually throw your map away!!

And don't forget when making a bid for equipment - you can't possibly go into upland areas without the additional safety of a navigation device!

Some issues

Most handheld GPS units will not be happy working in wooded areas or in urban canyons. Under these circumstances a bluetooth unit offers more chance of fixing a position.

Handheld GPS units eat batteries extremely quickly regardless of the manufacturer's specifications. It's probably best to invest in rechargeables.