A descriptive, mixed methods study investigated learning outcomes and processes of integrating environmental education (EE) and science education (SE). Specifically, this study examined the impact of EE-based constructivist science teaching approach on students' science achievement scores, environmental self-efficacy, course completion rate, and perceptions of their learning experiences. Participants of the study (N=46) included students in a Physical Science course at one public high school in a southeastern state of the United States. Data sources included the students' final exam scores, standardized unit test scores, self-efficacy measurements, course completion data, and student written reflections. Data analysis indicated that students with an EE-based constructivist science teaching approach (N=23) performed higher on science achievement tests and developed statistically higher environmental self-efficacy than those in a traditional teaching classroom (N=23). More students passed the final exam (96%) and the mean final exam score was four points higher (82) in EE-based constructivist teaching approach classes. Students who were in the EE-based constructivist science teaching approach classroom tended to perceive their learning experiences in more positive ways.