Whole group discussions are a key aspect of the NGSS because these activities are where students collectively make sense of natural phenomena. However, curriculum can present all discussions as possessing the same instructional purpose and roles for teachers and students. This can send the wrong message to teachers as to how to effectively engage their students and help develop their science ideas. To address this challenge, we present a framework for the three types of discussions that occur regularly in NGSS-aligned science classrooms. The three types of discussions are: initial ideas, building understandings, and consensus discussions. This framework highlights the different but complementary instructional purposes of these discussions and clarifies how teachers and students can effectively engage in each type. We believe this Discussion Types Framework can help teachers to better understand, plan for, and teach the different types of discussions that are integral to an NGSS-aligned science classroom. When teachers can think about the main goal of their discussion, they can use different back-pocket questions and facilitation moves that will help them to elicit student thinking, position students’ ideas relative to each other, and develop the entire class’s understanding.