A national plant and animal phenology observation program enabling participants to provide valuable observations that scientists, educators, policy makers and resource managers can use to understand how plants and animals are responding to climate change and other environmental changes. Phenology refers to recurring plant and animal life cycle stages. It is also the study of these recurring plant and animal life cycle stages, especially their timing and relationships with weather and climate. Nature's Notebook offers opportunities for observing plants and animals, digitizing archival data for the North American Bird Phenology Program and sharing phenological plant or animal data taken by volunteers prior to joining the project.