The purpose of this activity is for students to organize shape cards into three categories and name the categories. Students describe how they sorted and how many shapes are in each category. This sorting task gives students opportunities to analyze shapes closely and make connections (MP7). Students create a representation of how they sorted in the next activity.
Monitor for different ways groups choose to categorize the shape cards, but especially for categories that distinguish between pattern, number of sides or number of corners.
As students work, encourage them to refine their descriptions of the shapes on the cards using more precise language and mathematical terms (MP6).