ABSTRACT Research has highlighted the significant decline in teachers’ implementation of newly acquired teaching practices following professional development (PD), primarily attributed to the absence of follow-up support. Even science teachers who have participated in intensive PD programs often encounter challenges in integrating new teaching practices into their classrooms. This study investigated the impact of a follow-up PD (PD 2) on 16 rural middle and high school science teachers and their students’ outcomes after their participation in an intensive PD the previous year (PD1). The findings showed that the teachers’ inquiry knowledge and confidence levels in teaching science remained stable or slightly improved up until the end of year 2, comparable to the levels measured at the end of year 1. Moreover, teachers who initially showed lower levels of knowledge and confidence were more likely to revert to their initial status after reaching a certain level during PD1. Regarding student outcomes, the posttest effect sizes for middle school students were substantial and statistically significant in both year 1 and year 2, compared to their pretest scores. While the effect sizes for high school students in year 1 were small, they became larger and significant in year 2. The findings suggest the practical advantages of implementing follow-up PD to provide continued support for teachers’ implementation in subsequent years. Additionally, this study presents a sustainable and cost-effective approach to deliver follow-up support to teachers, namely through a short-term PD accompanied by distance-based peer instructional coaching.