Geocaching and Education, part 12 - Absolute and Relative Location

This is post #12 in a series of free resources for educators interested in using geocaching in education and other community groups like scouts or camps. The material is pulled directly from Educaching GPS Based Curriculum for Teachers. If interested in more resources, check out www.educaching.com.

Sincerely,

Jason Hubbard, Author

Absolutely Relative or Relatively Absolute – This activity allows your students to understand the difference between absolute location and relative location. Absolute location is what we use to describe an exact location. For example, 27979 White Road, Perrysburg, OH 43551 is an absolute location. Absolute location can also be found using waypoints in a GPS receiver---it is an exact spot on the map. Relative location involves a slightly less precise way to locate something, but we use it all the time. When we are telling someone how to find a gas station we say, “It’s two blocks down, then turn right, go over the railroad tracks and you can’t miss it. It’s beside the post office.” Relative location is described in great detail through the use of distances, directions, amount of time taken, and landmarks along the way. This is an important activity, because your students will be employing skills in both when they are Educaching. For example, when on a hunt, they use absolute location (coordinates) to find an Educache’s spot, but will also receive clues using relative location (i.e. under the rock, beside the tree, about 300 feet from the front doors of the school, etc.). Let’s use Educaching to teach the concept to your students by setting up a hunt that requires them to use both. To make things simpler, this will be a group hunt similar to the activity on Day 1. You will hide two Educache containers. The first one will be a small container with a set of directions inside to get to the second Educache. The students will use coordinates and their GPS to get to the first Educache (absolute location) and descriptive directions to reach the second (relative location). Find a hiding spot for the first Educache, then from that spot, look to see where you will place the second. Be creative! How can you describe how to get there? For example, will the students count paces? Will they head in a specific direction, like Northeast? Will they look for any signs or landmarks on the way? Try combining several of these clues to get the group from the first Educache to the second. Test out your directions by walking the path to your second Educache spot. Write these directions down and place them in the first Educache container and hide it in the first spot. Be sure to mark the waypoint in your GPS receiver to give the students these coordinates. Then, hide the second Educache in its spot containing a rewarding message to congratulate the students.On the day of this hunt, explain to your students the difference between absolute and relative location and have them give examples. Explain that they will use both in Educaching. Group your students so that they can share the GPS receivers, and give them the coordinates of the first location to input in their receivers now. Take the students outside and seek the first Educache together. When it is found, choose a student to open the container and read the directions one step at a time as the group follows the directions. Note: You may have to explain what a “pace” is if you used the word in your directions. Usually a pace is the distance covered by one step, or approximately three feet. Work as a large team to follow the directions carefully to the second Educache. The students may find that they need only to use the GPS to find compass bearing. As long as they are moving, the compass pointer on the GPS receiver will tell them the direction they are heading. When the students reach the area of the second Educache, tell them to look around for any good hiding spots where it might be. When it is found choose a student to open it and read the message inside. Before finishing this activity, review how absolute and relative location was used in this hunt. Also, see if the students can use their GPS receivers to calculate the distance between the two hidden educaches. Measurement is a vital skill used in most of the math lessons, and this would be a great point to have a mini-lesson on the topic.As a variation, you may want to have each small group look for its own educaches. This will require more preparation on your part, but will lead toward student independence. In this case, bring the students inside the classroom immediately afterward to discuss their successes and challenges with finding their educaches.