This article reports on a case study that examined the evolving thoughts and beliefs about corrective feedback of graduate students in applied linguistics, who were enrolled in a semester-long second language acquisition (SLA) course. Working in groups, the graduate students (students in an MA-TESL program, and doctoral students in a related program; a combination of practicing and prospective language teachers), conducted a partial replication of Lyster and Ranta's (1997) study of corrective feedback in some of their own ESL classes. The present study was designed to discover the extent to which graduate students' participation in this classroom-based research replication would contribute to a re-examination of their ideas, thoughts, or beliefs about corrective feedback. The replication project was conceptualized by the researchers as serving as a bridge between formal research and practical inquiry (Richardson, 1994). Analysis of multiple data sources (e.g. questionnaires, journal entries, a group interview) indicated that a number of students' ideas about error correction shifted throughout the semester. In particular, after participating in the research replication project, many students' comments revealed a decreased emphasis on the affective dimension of error correction, and a more sophisticated understanding of corrective feedback, as well as an appreciation for the relationship between corrective feedback, student uptake, and error type. In addition to themes of shifts in awareness about the complex nature of corrective feedback, the analysis further identified possible changes in future teaching practice, different attitudes toward research, and the appropriation of terminology pertaining to teaching. (Contains 2 tables and 16 notes.)