Problem-based learning (PBL) is a teaching/learning strategy through which students learn course content by solving real-world problems associated with the course material. Although the benefits of PBL have been amply demonstrated in the medical field and other selected subject areas, few studies have examined PBL's potential contributions in subjects that combine content from multiple disciplines. To address this issue, the current study explored the differential effects of PBL versus lecture-based learning on the achievement, problem-solving skills, and attitudes toward instructional strategies of undergraduate students enrolled in a newly created environmental biotechnology course. Data collected through quizzes, scenarios, surveys, and interviews revealed greater achievement, problem-solving skills, and positives attitudes toward the learning process of students exposed to PBL. Potential implications are discussed. (Contains 1 table.)