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Investigation: Geocaching

Lesson

    

Introduction to geocaching

Geocaching is a treasure hunt, in which participants use a GPS enabled device to hide and seek containers, called "geocaches" or "caches", at specific locations marked by coordinates all over the world. You can find a geocache near your home, in the city, in the bush, underwater or on vacation in a distant location.

The caches themselves vary in size and difficulty to locate. They could be small and well hidden tokens with a code or a large container with items to trade inside.

Common types of geocache hunts include:

  • A Traditional cache is the most common type and consists of a container with a logbook. Exact coordinates where the cache is located are given.
  • Multi-cache consists of one or more stages, each of them containing the coordinates for the next one; the final stage contains a physical container with the logbook.
  • An Offset cache is a type of multi-cache in which the initial coordinates are for a location containing information that encodes the final cache coordinates. An example would be to direct the finder to a plaque where the digits of a date on the plaque correspond to coordinates of the final cache.
  • Mystery/puzzle caches require one to discover information or solve a puzzle to find the cache.
  • Moving/travelling caches are found at a listed set of coordinates. The finder hides the cache in a different location, and updates the listing, essentially becomes the hider, and the next finder continues the cycle.

More information about geocaching and a more complete list of types of caches can be found here

 

Task 1: Find a cache near you

Let's first find a few caches in your area. This will give you some ideas about what makes a great cache and how the system works. 

A great place to start is Geocaching Australia. Read through the frequently asked questions at the top of the page and then use the map to zoom in on caches near you. 

Example of caches found in the Adelaide region

Symbols on the pins represent the type of cache located. Click on a location pin and follow the link to find out more information about the cache such as difficulty, logged finds and clues.  For a traditional cache the exact coordinates will be given and this can be copied into google maps or similar to help you locate the cache. 

As a start try traditional caches that are low in difficulty. There are also geocaching apps available for phones you can investigate.

 

Task 2: Design a geocache hunt

Let's create our own multi-stage geocache hunt around your school. We will not use the geocaching website to log these hunts as we don't want to create public caches on school grounds. We will design the caches to be located by other students in your class or in other classes at your school for a limited time so we don't have to maintain the cache.

Let's create a 3-stage puzzle hunt. With the following stages:

  1. The exact coordinates for the location of the first cache should be given.
  2. The cache at the first location should give a puzzle with an answer to unlock the coordinates for the second location.  
  3. The cache at the second location should give a puzzle with an answer to unlock the coordinates to locate the final cache.

Steps: 

  • Break up in to groups of 3-5 people.
  • What will you use as cache containers? 
  • Discuss what would be some great things to put in the final ‘cache’ as a reward.  
  • Discuss where would be some great places to hide geocaches around the school. Remember we need 3 places.
  • How could you disguise the cache so that it is trickier to find?
  • What puzzles will you use at location 1 and 2? These should give a one number or word answer that can be used to unlock a file with the exact coordinates for the next location. Perhaps a mathematical puzzle?
  • Hide your geocaches and record the exact coordinates, for locations on a small scale such as this you will need to record many decimal places for the latitude and longitude. These can be found using a gps device or google maps. For example dropping a pin in google maps (Right-click and select "What's here?") will show the location with 6 decimal places. Be sure to zoom in to select the location with a high degree of accuracy if using google maps without location active.
  • Put the exact coordinates in three separate files and lock file 2 and 3 with a password (the answer to your puzzles). Most documents such as word, pdf or OneNote have the ability to password protect. These should be placed on a shared location or emailed to the students involved in the hunt.
  • Once set-up, exchange the coordinates of the first location with another group and HAPPY HUNTING!

 

Tip: To make caches easier to hide and unlikely to be found or tampered with by muggles(those not on the hunt) you can use a small coin or token engraved with a code (number or word) that can be padlocked to a location. The code can be given to the hunt creator as proof you found the cache and they can then give the next puzzle or final cache treasure box.

 

Extension

Use the coordinates of your cache locations to determine the distance to travel between locations. This can be done using a gps enabled device, an online calculator or google maps. Can you develop clues that involve the distance? 

Outcomes

ACMEM159

locate positions on Earth’s surface given latitude and longitude using GPS, a globe, an atlas, and digital technologies

ACMEM161

find distances between two places on Earth using appropriate technology

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