Background: Nationally, a framework for H/O education for IM residents that is simultaneously clinically relevant, concordant with the ABIM Blueprint, and efficient in delivery is lacking at the graduate medical education (GME) level. At our institution, based on feedback from our residents we recognized an opportunity to innovate the H/O curriculum through active learning approaches to better meet the needs of our residents. Methods: Adopting the Kern Model of curriculum development, a needs assessment was performed to gauge resident opinions on the current H/O didactics and towards active learning approaches. Survey results informed the development of 4 FC modules, meant to seamlessly integrate into the existing didactics of morning report (MR) and noon conference (NC). Each module consisted of a video on a cancer type viewed during MR, cased-based activity during NC, and an instructor's guide. Following the Kirkpatrick model, resident opinions were assessed via surveys and feedback sessions. Pre/post-tests at 3 time points were used to assess learning. Standardized patient encounters (SPEs) with clinical competency scoring scales were developed to assess clinical reasoning skills. Results: 43% of residents (33/76) completed the needs assessment. A majority of respondents (82%) indicated the existing H/O didactics did not provide enough foundational knowledge. 87% of residents indicated a need for more active learning and 72% expressed interest in a FC approach. 43% (33/76) of residents attended ≥1 session (NC or MR). Post-intervention, 81% of residents strongly agreed the FC modules were relevant to clinical practice and board exams. 93% of residents strongly or somewhat agreed it was feasible and manageable to incorporate the FC format. Pre/post-test results showed statistically significant improvement in scores from before to after viewing the MR video (1-way ANOVA, p<0.011) with a medium effect size of 0.11. Significant change was not seen when the same test was taken after the case-based NC activity (p=1). Clinical competency scores from SPEs of full-participant residents were significantly higher compared to residents who did not participate in a FC module (t-test, mean 8.4 vs. 6.2/10, p<0.001). Conclusions: Our pilot H/O FC curriculum was overwhelmingly viewed as favorable and reported as clinically relevant, feasible, and manageable by our residents. Pre/post test results suggest that viewing the pre-session video during MR resulted in significant learning as compared to attending the case-based session during NC. Superior performance on SPEs by residents attending in full as compared to non-participants provides strong evidence supporting our modified FC approach in improving clinical reasoning skills. Overall, our study supports a broader application of our innovative FC model into existing traditional lecture-based resident H/O curricula.