We describe one of the eight units of a professional development program, the Numeracy Infusion Course for Higher Education (NICHE), which introduces research on cognition, including dual-processing theories, to university faculty. Under the dual-processing framework, System 1 (intuition) quickly proposes intuitive answers to judgment problems as they arise, while System 2 (deliberation) monitors the quality of these proposals, which it may endorse, correct, or override. We present several classic questions that demonstrate the pitfalls of overreliance on intuition without analytical thinking, then describe faculty participants’ responses to these questions and their ideas on how to apply cognitive illusion research to quantitative reasoning instruction. The unit has helped generate excellent ideas for quantitative reasoning instruction. A persistent concern shared by many participants, however, is that weakness in basic mathematics and language comprehension among urban public university students might present a challenge in implementing these ideas.