This project aims to serve the national interest by exploring strategies to support student retention of important mathematical skills from key introductory courses. This project centers on the Keep in School Shape (KiSS) program at Arizona State University, which provides students with opportunities to regularly engage with foundational course material over academic breaks or unplanned disruptions in their schooling. Keeping key skills up-to-date during these periods will help students maintain critical skills over times when school is not in session. The program uses existing, readily available online survey software to send students daily review activities, resources, hints, solutions, and empowering feedback messages via text or email. In the context of an introductory calculus course sequence at the university level, this project explores the outcomes of participation in the KiSS program. The approaches used to support students through this project are cost-effective and have potential to inform other efforts to support students outside of traditional periods of instruction in disciplines outside of mathematics. <br/><br/>The goals of this project include an exploration of how engagement with review activities impacts student outcomes, how students respond to various incentive systems, and how students engage with support opportunities over academic breaks. Project research will randomly allocate participants to treatment conditions and compare their outcomes to comparable nonparticipants. By exploring short- and long-term outcomes of the review program, this project hopes to set the stage for understanding how best to design outside-of-class supports that both appeal to students and help them achieve success in their chosen field of study. The project will also investigate how individual accolades and varied incentive structures can impact students' motivation and engagement. Research and project evaluation outcomes will be disseminated broadly to communities of interest, with an emphasis on adapting the KiSS program to other institutions and disciplines. The NSF IUSE: EDU Program supports research and development projects to improve the effectiveness of STEM education for all students. Through its Engaged Student Learning track, the program supports the creation, exploration, and implementation of promising practices and tools.<br/><br/>This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.