I've been doing a whole bunch of lame and boring labs for my ecology students, and I've had it with my lab manual. For the rest of the semester, I'm doing cool labs.. next week, I've decided on a GPS scavenger hunt (geocaching). Do you have any ideas for something cool I could hide? Or if hiding actual objects seems like a bad idea, what should I hide as a marker for them to bring back, and what should the prizes be for finding things? Furthermore, any other cool labs you can think of that would actually be FUN for an eco class? I have a few ideas, but I'd love to hear more.