The purpose of this True or False is to elicit strategies students have for adding within 100 using methods based on place value. As students reason about how to add the digits in the two addends, they make use of base-ten structure (MP7).

• “How can you explain your answer without finding the value of both sides?”

The purpose of this activity is for students to interpret equations that represent different methods for addition. When students connect the quantities in the story problem to addition equations, they reason abstractly and quantitatively (MP2). Base-ten drawings are provided for Jada and Kiran's way so that students can use the drawings and the equations to make sense of the different methods. Students compare methods that add tens and tens and ones and ones to methods that add on by place. Students may also relate the methods used by Kiran and Tyler to the make 10 methods they use when adding within 20.

This activity uses MLR8 Discussion Supports. Advances: listening, speaking

The purpose of this activity is for students to find the sum of 2 two-digit numbers using one of the methods students have seen in previous activities. Students choose which method they would like to use and show their thinking using drawings, numbers or words. Although students have been analyzing base-ten drawings, if they are ready to represent their addition methods with equations, they should be encouraged to do so. Students participate in a Gallery Walk in which they observe the different ways the addition methods can be represented.