As part of the curriculum in New Mexico, we teach a unit on Ecosystems (food webs, consumers, producers, herbivores, carnivores, photosynthesis...etc...) and at the end of the unit, we take a trip to the SANDIA MOUNTAINS NATURAL HISTORY CENTER. The kids go on a two hour hike, take leaf rubbings, look at animal tracks, and skat (animal poop...which is the highlight of the trip) and learn about the trees and animals of the high desert.
They get to spend all day outside, even having their lunch outside. Some have never been to the mountains, much less hiking. They really enjoy it and they learn a lot. Here are a few photos of us resting at the top of the mountain. The tall guy is our guide and teacher for the day, Jim.
It's very structured and safe and it keeps their attention focused all day. On the bus ride back they are usually exhausted and a lot of them fall asleep.