This study examines the feasibility of adding a proximal outcome survey to a book distribution program. We also examine access to books at home for Grade 3 to 5 students experiencing poverty and relations with reading motivation and reading amount. Finally, we describe students' book preferences by analyzing the difficulty and genres of texts they select for outside of school time (OST) reading. We surveyed 549 students attending four elementary schools that serve > 98% economically disadvantaged students using this new measure. We found adequate feasibility and initial validity of this short survey. Key findings from this study were that students who had access to a greater number of books at home read more during OST, even after adjusting for reading motivation. Consistent with past research, students' reading motivation related to their reading amount. We discuss potential implications of these findings for book distribution efforts.