The decline in hummingbird populations and shifts in their movements may adversely affect their role as pollinators and, in turn, plant biodiversity (Allen-Wardell et al. 1998). For example, Hadley et al. (2014) discovered that larger fragments of forest correlated with larger hummingbird populations and more seeds of "H. tortuosa" being produced. Citizen science engages people to collect, organize, and analyze scientific data at a scale beyond the capabilities of a single research lab. Due in part to the explosion of connectivity technology and social media, research projects using citizen science have increased dramatically, and citizen scientists have contributed to furthering understanding in a wide range of fields, from ecology to computer science (Bonney et al. 2014; Rosner 2013). Working as citizen scientists, students can collect and report data for projects beyond the classroom and actively contribute to furthering scientific knowledge (Jones et al. 2012). This article describes a project to support hummingbird conservation, in which the Oregon State University Citizen Science Hummingbird Project (OCSHP) uses student citizen scientists to better understand the populations and habitat preferences of rufous hummingbirds and other common hummingbird species in Oregon (Figures 2 and 3, p. 28). The OCSHP aims to determine whether--like the tropical species examined by OSU researchers--temperate hummingbirds are sensitive to deforestation and forest fragmentation. Several species of tropical hummingbirds prefer large patches of connected forest and tend to travel in forested habitat while avoiding open areas (Volpe et al. 2014). The OCSHP was started in 2012 through a National Science Foundation (NSF)-funded research project. The principal investigators of the study partnered with the Oregon Natural Resources Education Program to include citizen science studies in Oregon that paralleled the research questions of the NSF-funded study. The goal of the OCSHP is to have students build a data set to help determine whether changes in forest cover and human development lead to hummingbird decline.