The purpose of this Warm-up is to introduce the students to the Which Three Go Together? routine, which will be used throughout the year. This routine gives students a reason to use language precisely (MP6). It gives the teacher an opportunity to hear how students use terminology to talk about characteristics of the shapes in comparison to one another. In this Warm-up, students work with three images of teddy bears and explain which two go together. By the end of the section, students will compare four images of shapes. Emphasize to students that there is no right answer to the question and that it is important to explain their choice. Listen to how students create an argument and use or revise language to make their argument clear. During the rest of the year, this Warm-up routine will have four choices, and students will choose which three go together.

• Display Images A and C.
• “Mai said these teddy bears go together because both are holding a heart and the other one isn't.”
• Display Images B and C.
• “Diego said these teddy bears go together because both are fuzzy and the other one isn't. What do you think?” (Both Mai and Diego are correct.)
• If needed, say, “There is more than one correct answer. We can find reasons why different teddy bears go together.”