Students often participate in a myriad of academic support programs offered during the first year of college. This study is an investigation of the effects of participation in multiple high-impact educational practices on academic success outcomes (cumulative GPAs and persistence rates) among 2,028 first-year students. Results suggest that the synergy of multiple high-impact practices (HIPs; e.g., first-year seminar, learning community with service-learning experiences) contributes to students' academic success more than HIPs in isolation or no participation. Findings also suggest that participation in a summer bridge program, designed to create readiness for HIPs, enhanced the effectiveness of the experiences. Results from an instrumental variable (IV) analysis indicated that the positive outcomes associated with participation in the summer bridge-HIPs intervention were not completely explained by self-selection bias.