Full Day School extends students’ time at school, but additional instructional time does not automatically guarantee meaningful learning. This study aims to systematically synthesize evidence on how FDS is translated into learning design in Indonesian elementary education. A Systematic Literature Review (SLR) was conducted using studies published between 2018 and 2025. Literature was identified through Google Scholar and selected using predetermined inclusion and exclusion criteria, followed by identification, screening, eligibility assessment, and inclusion based on the PRISMA framework. Sixteen articles were included in the final synthesis and analyzed thematically across five dimensions: organization of extended learning time, learning activity design, teacher pedagogical adaptation, student engagement and learning experience, and curriculum alignment and contextual conditions. The findings indicate that the educational value of FDS depends less on the duration of schooling than on how additional time is organized into varied, active, and meaningful learning experiences. Teacher creativity, pedagogical adaptation, curriculum alignment, school management, infrastructure, and parental support further shape implementation quality. The study contributes a pedagogical perspective by repositioning FDS as a learning-design challenge and provides a basis for developing more purposeful and context-sensitive extended-day learning practices.