The purpose of this activity is for students to write equations that represent the number of objects in the rows or columns of an array. In a previous lesson, students matched arrays to expressions. In this activity, they write their own equations and describe how each equal addend represents the number of counters in each row or each column.

• “How do the addends in your equation match your array? How does the number of addends in your equation match your array?”
• “What should you change to make sure the sum matches the total number of counters in your array?”

• Invite previously identified students to share their equations and ask others to decide how many rows and columns each student’s array could have.

• “How does your representation show how to plant the crops?”
• “How could you arrange the crops so there are at least 2 rows?”

• Invite 2–3 previously identified students to share how they arranged 16 carrot seeds. Select the student who arranged in 4 rows of 4 carrots seeds last.
• If no student arranged the carrots seeds in 4 rows, arrange counters to show 4 rows of 4 counters.
• “What equation would represent the array using equal addends?” ()
• “Do the addends represent the number of carrot seeds in each row or in each column?” (It could represent both.)
• “Can you find another equation that shows the number in each row or each column?” (No, since there are the same number of rows and columns, there is only one equation.)