The purpose of this activity is for students to relate dot images to addition expressions. In a previous lesson, students discussed using addition expressions to show putting together the two values represented by two dot cubes. In this activity, students match expressions to dot cube images and find the total, either by using the dots in the image, or by finding the value of the expression. Students then create matching dot images and expressions. When students match dot images and expressions and write expressions to match dot images, they reason abstractly and quantitatively (MP2).

• “¿Cómo supieron cuál expresión le correspondía a cada par de dados de puntos?” // “How did you know which expression matched each pair of dot cubes?” (I counted the dots on the first dot cube and wrote the number underneath, then counted the dots on the second cube and found the expression with those numbers. I’ve seen these dot patterns before, so I just knew that the first cube shows 4 and other shows 3. So, I found the expression that adds 4 and 3.)

The purpose of this activity is for students to revisit Stage 1 of the Check It Off center, which was first introduced in IM Kindergarten. In this activity, students are introduced to the term "sum."  They take turns picking two number cards (0–5) and finding the value of the sum of those two numbers in a way that makes sense to them. Students check off the number that represents the value of the sum (0–10) on their recording sheet and then fill in the addition expression. The partner who checks off the most numbers wins.

MLR8 Discussion Supports. To give all students an opportunity for verbal output, and to support the transfer of new vocabulary to long-term memory, invite students to chorally repeat phrases that include the term, “sum” in unison, 1–2 times. For example, “La suma de 1 y 3 es 4” // “The sum of 1 and 3 is 4.”

• Display number cards 4 and 3.
• “¿Cómo podemos encontrar la suma de estos dos números?” // "How can we find the sum of these 2 numbers?"
• Invite previously identified students to share.
• “¿Qué expresión de suma podemos escribir para representar la suma de estos números?” // "What addition expression can we write to represent the sum of these numbers?" ( or )