Here are a few resources to help with geocaching...
The first article is about teacher geocaching groups - http://blog.geocaching.com/2011/12/new-teacher-tools-geocaching-and-education/
How to go geocaching:http://www.wikihow.com/Go-Geocaching Geocaching Websites: http://www.cacheopedia.com/wiki/Geocaching_websites
Family treasure hunting with your family! http://www.squidoo.com/Geocaching-family-fun Geocaching.com: http://www.geocaching.com/
Getting started with Geocaching with your students: http://blog.discoveryeducation.com/blog/2011/05/16/getting-started-geocaching-with-your-students/
Want some more resources to get you started? Here are just a few: Geocaching with Kids : http://eduscapes.com/geocaching/kids.htm
Geocaching and Education: http://forums.groundspeak.com/GC/index.php?showforum=103