The first author's initial attempts at a whole-class mathematics discussion were woefully dysfunctional. Ten second graders showing their answers to a missing addend question about the number of children left riding a school bus did not result in the mathematical epiphany that the textbook promised. She did not give up on using mathematical discourse in my classroom; she knew students needed a platform to voice their mathematical ideas. So she kept at it, adjusting this and that until she had a predictable, productive routine that allowed children to safely express their mathematical ideas.