TRAVERSE CITY -- Sergei Kelley told his parents his fourth-grade class was learning about latitude and longitude, and his mom knew just how to help get the kids excited about the geography concepts.
She'd introduce them to the outdoor treasure-hunting game of geocaching.
"There's really no tangible ways of teaching longitude and latitude," said Paula Kelley, who with her husband Dave recently shared with the Old Mission Elementary School class their family's interest in the Global Positioning System (GPS) activity. "We hid caches in the woods around the school, and the kids really seemed to like it. It's going to be something we do every year for the fourth-graders."
Throughout northern Michigan, the country and the world, geocaching continues to gain momentum. Adventure-seekers of all ages are eager to locate and hide what are typically small, waterproof containers that hold a logbook and treasure of some kind -- typically toys or trinkets. There are more than 685,000 active geocaches worldwide, according to www.geocaching.com, which bills itself "the official global GPS cache hunt site."
Local enthusiasts estimate more than 1,000 registered caches in the Traverse City area.
The sport of geocaching began in 2000, when Oregon computer consultant Dave Ulmer used his portable GPS navigational receiver to hide a bucket of prizes in the woods and left Internet clues to allow other GPS users to find them.
The game works through players setting up and concealing a cache, recording the GPS coordinates and posting them on www.geocaching.com. Others use the coordinates to find the cache, which sometimes contains rewards -- perhaps a trinket or postcard. If you take something out of a cache, you're expected to leave something else in its place. Successful players then sign the log book, conceal the cache again and contact the Web site to tell the story of how they found it.
Bill Muth, of Traverse City, tried geocaching in 2002 after his wife Mary gave him a GPS device as a gift around the time the couple moved from Washington to northern Michigan.
"(Geocaching) took us to a lot of neat places we wouldn't have gone to otherwise," he said. "At that time, it was getting us out to the Brown Bridge area, along the Boardman River. Geocaches are hidden everywhere, and it was very nice because it helped us learn our way around."
Muth figures he's found 400 caches and hid 40 of his own through the years.
"Not only is it fun to get outside, it's fun to get on the Internet and see how clever people can be in hiding stuff," he said. "Sometimes people will have puzzles to solve to get the coordinates. There's a lot of variations."
The Kelley family, which also includes 7-year-old daughter Lera, tried geocaching for the first time this summer and have since done it numerous times near their Old Mission Peninsula home and Mackinac Island.
"Mackinac Island is a great place -- it gets you around to the back side and interior where no ones thinks to go," Kelley said.
They've even incorporated the hobby into a recent trip to Germany and Austria. In their search they stumbled upon "a very nice park, a huge natural area" they wouldn't have found otherwise, Kelley said.
"It's become a way to explore the area, especially if you are not familiar with the area," she said. "We all kind of got hooked on it. My daughter likes the hiding part of it and my son likes the technical part, reading the GPS."
Jensen Kurtz, of Traverse City, also discovered geocaching this summer.
"We have a great time doing it. It's an inexpensive, fun family thing to do," said Kurtz, who has gone several times with wife Tracy and children Nick, 12, and Audrey, 8.
The family mostly enjoys locating treasures, but hid a cache on an island on Long Lake that recently was found.
"We hid rubber bath tub style toys and we put a paper plate in there (for a log book)," Kurtz said. "They wrote down when they found it and what they took, what they left and what time it was. I like hiding, I think that's pretty neat. I think the kids get a big kick out of the treasures."