We discuss an implementation of the research-based Pathways precalculus curriculum in a large-lecture format supported by recitations, clickers, and online homework. We describe our approach to adapting the implementation of Pathways precalculus from a small class to a large lecture instructional format. We report data on student learning and retention before and after this Pathways implementation which show improved student success in precalculus, improved student retention in calculus, and significant shifts in student understanding of precalculus ideas that are foundational for learning calculus.