Environmental problems are increasing day by day, and their effects directly affect our lives. The only solution for the elimination of these problems is a conscious society. A conscious society is possible with a solution-oriented education that starts at an early age, includes all disciplines, addresses real-life problems, and focuses on solutions. In this convenience sampling research, 5th, 6th, and 7th grade students and teachers from different branches of a public secondary school in the 2021–2022 academic year were recruited. The opinions of the students and their teachers, who participated in an environmental education program prepared with a transdisciplinary approach for a sustainable world and implemented for a total of 9 months on seven themes, were taken. In this qualitative study using a semi-structured interview technique, a total of 30 students (15 girls and 15 boys), 10 from each grade level, and 10 teachers were interviewed. According to the findings obtained through content analysis, the program had positive effects on both students’ and teachers’ environmental knowledge, attitudes, and behaviors. In line with the results, it is recommended to implement a long-term program that includes all branches instead of studies in which environmental education is associated with a single course.