Flipped learning has been recognized as a promising pedagogical model for methodological progress in educational environments. Studies have shown the effectiveness of flipped learning when used with appropriate educational technologies and learning strategies. On the other hand, comprehensive guidance is required to combine this pedagogical model with new technologies. The current study investigates how discussion tools integrated into online flipped learning environments affect students' engagement and self-regulation. Participants targeted for this study consisted of 121 first-year students randomly assigned to one of four experimental conditions formed by a 2 (synchronous online discussions vs. asynchronous online discussions) × 2 (online flipped learning vs. online learning) factorial pretest/post-test design. The results revealed that there was a significant interaction effect between the online flipped learning approach and synchronous online discussions on behavioral and cognitive engagement. While no interaction effects on self-regulation between the learning approach and online discussions were found, the results revealed that the online flipped learning approach and synchronous online discussions separately increased self-regulation. The findings contribute to the online flipped learning approach by adding a new perspective, namely synchronous online discussions, and thereby proposing a new interactive learning experience for a more engaging and deeper exploration of online learning. The implications of designing an online flipped learning environment with synchronous online discussion tools are discussed.