If college science instructors are to use inquiry practices more in the classroom, they need both professional support to foster comfort with the pedagogy and practical ways to engage students in inquiry. Over a semester, we studied 13 community college biology instructors as they adopted bioinformatics problem-based learning (PBL) modules in their classrooms. The study used a diffusion of an innovation theoretical framework and a systematic model for examining faculty decision making around instructional materials adoption. To study faculty decision making, researchers created an online professional development community using an action research reflection-on-practice approach. Following an inquiry continuum model, faculty could choose from modules that varied by activity structure and problem complexity. Most instructors chose easier PBL modules with high structure and low complexity to avoid alienating students and conserve class time, and then observed that students could transfer knowledge to other tasks. As a result, they intended to expand use of inquiry in their classes.