This article examines the presumption that library research workshops will increase the quality, quantity and diversity of sources students use. This study compares bibliographies of research papers written by freshman composition students who received a library research session to those of students who did not receive any library instruction. Our data show that students who received workshops were more likely to use the specific library resources introduced in the session than those who did not receive an instruction session, but students did not use more sources, more diverse sources, or more scholarly sources.