Flipped instruction has been flaunted as a pedagogical strategy that supports improved learning and retentive abilities of students. Nevertheless, one of the twin challenges reported in the literature, students' failing to complete preparatory work, impedes the efficacy of the model. Thus, learners' motivation and attitude to work are essential for the successful implementation of the constructivist learning-centric approach. Yet very few studies have examined the connections between students' motivation and achievement goals in flipped instruction. To address the current gap, this study investigated the relationship between students' motivation beliefs, flipped method, and achievement in precalculus using pre- and post-course surveys collected from 32 undergraduates. Both motivation beliefs and flipped instruction influenced academic achievement positively in the course and were moderated by students' efforts. [For the complete proceedings, see ED630210.]