The C. Hart Merriam Elevation Gradient provides a common field installation for students to learn by participating in the research process, and facilitates introductory students in accumulating a foundation of basic knowledge that can be assumed when they enter advanced courses. By returning to the same field system in more advanced classes, students will spend less time learning the experimental system and progress more rapidly to the application of the basic knowledge from previous courses to new questions. In introductory classes such as ENV 230, students will learn how changes in temperature and moisture along an environmental gradient affect primary productivity, using the CHM Gradient as a case study. Then, when students return to the CHM Gradient in higher level classes, for example BIO 326L, they will see how outbreaks of insect herbivores modulate these environmental controls over productivity.