Problem-based learning (PBL) has gained credibility and some use in institutions of higher education. This paper provides a brief conceptual discussion of PBL and the idea of "problem," and describes one learning model that incorporates PBL as a method for moving students to high levels of learning. The second portion of the paper describes one attempt to use PBL in three middle schools and one high school, with a focus on teacher training and teachers' feedback on the program. Teachers reported that students lacked adequate social skills needed to process group work efficiently and effectively, and that girls tended to participate in group work more than did boys. Teachers also felt bound by the time demands of the program. However, PBL was an effective model for addressing varied learning styles, improved general classroom behavior, and made teacher-learning experiences more exciting. A conclusion is that PBL might not be the complete answer to school improvement; however, it permits flexibility, encourages communication and mutual respect, and showcases students' talents. Two tables are included. The appendices contain a summary of Getzels' three problem types, a matrix depicting change-process levels, and a summary of teachers' feedback. (Contains nine references.) (LMI)