This phenomenographic study documented changes in student-held electrical concepts the development of meaningful learning among students with both low and high prior knowledge within a problem-based learning (PBL) undergraduate electrical engineering course. This paper reports on four subjects: two with high prior knowledge and two with low prior knowledge. Subjects were interviewed at the beginning and end of the course to document their understanding of basic electrical concepts. During the term, they were videotaped while solving problems in lab. Concept maps were generated to represent how subjects verbally connected concepts during problem-solving. Significant to PBL research, each subject's body of meaningful learning changed with each new problem, according to how the subject idiosyncratically interpreted the activity. Prior knowledge among the four subjects was a predictor of final knowledge, but not of problem-solving success. Differences in success seemed related more to mathematical ability and habits of mind. The study concluded that, depending on context, meaningful learning and habits of mind may contribute significantly to problem-solving success. The article presents a testable model of learning in PBL for further research.