Sepanik has been involved in several evaluations during her tenure at MDRC, including the Enhanced Reading Opportunities impact study, professional development impact studies for second-grade reading teachers and seventh-grade math teachers, the evaluation of the Formative Assessments of Student Thinking in Reading program in Boston Public Schools, the Getting Ready for Success college-readiness pilot project in Tacoma, Washington, and an exploratory study of college-readiness partnerships in Texas. She has been responsible for managing quantitative and qualitative data collection, designing surveys and interview protocols, analyzing program effects, and coauthoring several reports. At present, she is director of the Diplomas Now Investing in Innovation evaluation, an impact study of a secondary school reform model, and the Advancement Via Individual Determination (AVID) College Readiness System evaluation, a developmental study of the AVID college-readiness program being implemented at three rural Florida school districts and the local community college. Before joining MDRC, Sepanik worked as a research analyst at Chicago Public Schools, conducting research on student access to quality teaching and supporting efforts to create a school accountability system for the district. She has also taught middle school language arts and social studies. She has an MPP from the Harris School for Public Policy at the University of Chicago.