I have a multicache in Petoskey, MI. that has a person do research on the internet (or elsewhere) to obtain answers to some questions about Petoskey, then do some simple math; find a local benchmark, and find the two cache stages. I also encourgae the seekers to make use of local maps, topo, or some such else as the river the cache trail follows tends to meander. This helps a seeker from wandering aimlessly around gravel piles, factories, etc.
Another idea would be to use a travel bug. I think travel bugs would be a great educational tool. One could use it to study geography, social sciences, statistics, and any number of analysis methods.