## Reflection: Conferencing Is it addition or subtraction? - Section 3: Independent Practice

An "Ah-hah" moment occurred on this video and I would like you to listen to Matthew's conversation. This student is not pictured in the video, but you can hear him describing what he realized in the audio. It is a conversation I am having in the background as I film another student working. Matthew shares that he knows addition has occurred because the answer is larger than the beginning number in the equation. During our whole group discussion I used problems on the board such as; 4 __2 = 6 and 9 __ 3 = 6, to ask questions like, "what hints are there in these problems to tell me it is addition or subtraction?" Some student noticed, but I had to point out to others that if the last number in the equation was larger than the first two numbers then it is addition. Also, if the first number was larger than the final answer, then it was subtraction. Using unifix cubes is a great concrete method to show them the part-part-whole relationship between these numbers. It was one of those light bulb moments and I was so proud of him for making this connection.

Conferencing: Student achievement

# Is it addition or subtraction?

Lesson 9 of 9

## Big Idea: Addition and subtraction facts are related, and my First Graders need more practice in using properties of operations to make decisions about equations. This lesson has them decide which operation is being completed to make the equation true.

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35 minutes

### Jennifer Moon

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