By simply asking students how they got the answer to a problem, math teachers can open the door to stimulating discussions in class. But how can they make sure those discussions promote mathematical understanding? Allison Hintz and Elham Kazemi explain that teachers need to know what the goal is for a discussion and plan accordingly. The authors discuss to kinds of math discussions: open strategy sharing and target sharing. Open sharing is the best technique to use when teachers want students to become aware of different ways to solve a problem. Targeted sharing is better when teachers want students to make sense of particular strategies. For example, a 4th grade teacher could have students share their answers to the problem 24 divided by 4 and explain how they got that answer. A follow-up discussion could compare two different ways students solved the problem and what those methods tell them about division. In all types of mathematical discussion, it's important that teachers treat students as mathematical thinkers, giving them opportunities to share, recording their responses, and allowing them to revise their responses as their understanding develops.