Part of the mission of the Education Department of the American Geological Institute (AGI) is to provide professional development opportunities on geoscience topics for K-12 teachers. AGI accomplishes this through a number of programs that include both face-to-face and online offerings. Face-to-face programs include week-long summer institutes for lead teachers from around the U.S. and beyond, as well as shorter programs during the academic year. Online offerings for teachers range from semester-long graduate courses for middle school teachers to professional development web sites, wikis and guides. This session will describe how AGI combines face-to-face offerings with online programs to support lead teachers, collect workshop implementation data and reach the widest possible audience of K-12 educators.