Background/Question/Methods The Montana ECOS Project (Ecologists, Educators, and Schools) is a GK-12 partnership to enhance teaching skills of graduate students in the sciences and to promote hands-on science education in K-12 schools (www.bioed.org/ecos). ECOS uses rural and suburban schoolyards and adjacent open areas in western Montana as outdoor laboratories for learning about the environment. One way we do this is through a yearlong Seasonal Schoolyard Science program to help teachers and their students explore seasonal change, or phenology. Over the academic year, students explored their schoolyards throught the seasons by exploring the questions, 1) Who's in our schoolyard?; 2) Where did they go?; 3) When will they come back?; and 4) How do we know? By the last month of school, students used the skills they developed throughout the year to ask their own questions about “What do I want to know next about the ecology of my schoolyard?” This phenology series also was designed to link closely with Project BUDBURST! (www.budburst.org), a national citizen science campaign to monitor plant phenology. This linkage provides another mechanism for teachers and their students to do real science in their schoolyards beyond the ECOS Project. Results/Conclusions The ECOS model has identified at least four elements that support sustainability of scientist-educator partnerships, to ensure continuation of our mission No Child Left Indoors: 1) Creating physical infrastructure to provide a lasting schoolyard laboratory for ecological investigations (e.g., native plant gardens, interpretive nature trails); 2) Developing sustainable web-based resources for educators, including extensive information about local ecology and hands on curriculum ideas (www.bioed.org/ecos); 3) Engaging the community through investment in their local schools and participation in ecological activities, such as schoolyard weed pulls; and 4) Establishing long-term partnerships between schools, organizations, and agencies. Additionally, we found that an integrated, phenological approach to ecological inquiry, which gradually led teachers and their students through the scientific method (and the seasons) and, ultimately, toward independent research projects related to Project BUDBURST!, proved an effective means of enhancing teacher participation in inquiry-based learning in the schoolyard.