National Park Service Ranger Jim Heywood gives students from GeoFORCE Texas an overview of the Grand Canyon after a hike down the canyon's Kaibab Trail.
Tenth graders from GeoFORCE Texas survey the Colorado River from the bridge over the Grand Canyon dam.
GeoFORCE Texas students Yonelle Aromin and Martha Ortiz, both tenth graders from Uvalde, Tex., stand above the Colorado River on the bridge over the Grand Canyon dam.
