This chapter works from a clear, research-based understanding of critical thinking in order to explain how debate can be used in the classroom to promote specific critical thinking skills. It demonstrates what teachers can learn from the critical thinking literature. The chapter reviews the existing critical thinking literature to explain how researchers have defined critical thinking as well as to raise important questions about how critical thinking is best taught. It suggests that, if education and communication researchers want to popularize debate across the curriculum, they should align their future research with findings in the critical thinking literature. Classroom debates can be scaffolded into content courses across the humanities, sciences, and social sciences, but time should be taken when introducing debate to emphasize aspects of critical thinking that the instructor wants to teach. Classroom debate practices often use ballot-writing as an activity to encourage audience judgment and to assess student skill at argument evaluation.