Increasing faculty use of active-learning (AL) pedagogies in college classrooms is a persistent challenge in biology education. A large research-intensive university implemented changes to its biology majors' two-course introductory sequence as outlined by the "Vision and Change in Undergraduate Biology Education" final report. One goal of the curricular reform was to integrate core biological concepts and competencies into the courses using AL pedagogical approaches. The purpose of this study was to observe the instructional practices used by faculty (N = 10) throughout the 3-year process of reform to determine whether the use of AL strategies (including student collaboration) increased, given that it can maximize student learning gains. Instructors participated in yearly interviews to track any change in their perceptions of AL instruction. Instructors increased their average use of AL by 12% (group AL by 8%) of total class time throughout the 3-year study. Interviews revealed that instructors shifted their definitions of AL and talked more about how to assess student learning over the 3 years of the project. Collaboration, feedback, and time may have been important factors in the reform, suggesting that small shifts over time can accumulate into real change in the classroom.