The purpose of this activity is for students to compare a Put Together, Total Unknown story problem and a Put Together/Take Apart, Both Addends Unknown story problem with a similar context. This is the first time that students have worked with a Put Together/Take Apart, Both Addends Unknown story problem.

• “What is the same about these stories?” (They are both about picking apples. They both have red and yellow apples.)
• “What is different about the stories?” (The first story is about Mai and the next story is about Lin. In the first story we knew how many yellow apples and how many red apples. In the second story we know that there are 8 apples altogether.)
• “In the next activity, we will work on showing what happened in the second story.”

The purpose of this activity is for students to make sense of a questionless Put Together/Take Apart, Both Addends Unknown story problem. In this activity, students are asked to show what Lin’s apples could have looked like. The focus of this activity is for students to show the two groups of apples, rather than on answering specific questions about how many red apples and how many yellow apples Lin had. While students may notice that there is more than one possible solution to the story problem, that is not highlighted until the next lesson.

When students explain to a partner how they have represented the apples they reason abstractly and quantitatively (MP2).

• Invite previously selected students to share.
• As each student shares, ask:
  • “How many apples did Lin pick?”
  • “Where do you see the red apples that Lin picked?”
  • “Where do you see the yellow apples that Lin picked?”
• “_____ used red and yellow counters to show Lin’s apples. What could I do if I wanted to draw a picture to show Lin’s apples?” (You could draw 4 red apples and 4 yellow apples. You could draw some circles. You could write "r" for red and "y" for yellow.)

The purpose of this activity is for students to choose from activities that offer practice composing, decomposing, adding, and subtracting numbers.

Students choose any previously introduced stage from these centers:

• What's Behind My Back?
• 5-Frames
• Make or Break Apart Numbers

• “One of the materials we use during centers is connecting cubes. How should we use connecting cubes during centers? What’s an example of how you saw a classmate using the connecting cubes to do math?”