assistance of a firm specializing in program evaluation to formulate and test metrics for the teaching with Primary Sources (TPS) program, as well as support the piloting of TPS teaching materials, in preparation for a summative evaluation to be conducted in 2009. Under the TPS program, 20 educational partners, including universities and school districts, conduct professional development for teachers focused on using Library of Congress digitized primary sources in instruction. Teachers who progress to the second level of the TPS program create teaching materials based on primary sources from the Library for dissemination to other teachers.