Collaboration between school libraries and classroom teachers can have a powerful impact on student learning. School librarians routinely collaborate with English language arts and social studies curriculum and less frequently with areas in STEM education. This research examines middle school mathematics teachers' extent of or willingness to collaborate with the school librarian in one large urban Midwestern school district. This quantitative descriptive study sought to answer the question "What factors influence middle school mathematics teachers' extent or willingness to collaborate with school librarian?" This research looks at, from the middle school mathematics teacher's perception, the roles and responsibilities of the school librarian. Specifically, this study looked at the professional library skills, instructional and teaching abilities, and the professional disposition of the school librarian to determine if these factors had any influence on the middle school mathematics teachers' extent or willingness to collaborate. This study was conducted through the lens of the theory of social constructivism. Data was collected through an online survey of one district's middle school mathematics teachers. Results of the research showed several things: 1) participants had an overall positive perception of the school library, 2) participants were often unaware of the resources and services available to the mathematics curriculum, 3) currently there is a low incident of collaboration between mathematics teachers and librarians, and 4) a majority of participants would be willing to collaborate with the school librarian in the future. The results of this study have implications for school library professional development and school library preservice training. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]