Adult-focused natural resources education is critical amid widespread challenges related to water quality, biodiversity declines, and climate change. Extension educators are poised to make impactful advances in natural resource education among adult learners when equipped with educational tools that improve knowledge and build connections among peers. The Mater Conservationist Program in Iowa sought to address this educational need through a flipped-classroom learning model evaluated in this report. Participants (n = 174) enrolled in 11 offerings of the program completed a multi-week educational curriculum that combined online instruction by university educators with in-person instruction led by local natural resources professionals and extension educators in a flipped classroom model. The approach ensured a standardized educational experience across the state but allowed for tailored, locally-focused education through in-person instruction on topics most important or relevant to local natural resource issues. Participants completing a post-course evaluation indicated widespread satisfaction (91% extremely or somewhat satisfied) in all three program elements -- online instruction, in-person instruction, and networking opportunities. Participant self-assessed knowledge increased in each module topic between 2.8 and 3.8 points on a 10-point scale (P < 0.001). Participants declared an intent to apply lessons from the class on over 30,000 acres of land they owned or had influence over across a diversity of land use contexts found in the state. The flipped classroom model facilitated deep learning but also important experiences in nature and networking among peer learners and professionals that should translate to improved community engagement in critical areas of natural resources stewardship.