## Reflection: Conferencing Subtracting from Nines - Section 3: Student Practice

Having student conferences with students was one of the most powerful ways to check for student understanding during this lesson. First, I wanted to make sure students could successfully use the strategy. All students were able to do this! Next, I wanted to check to see if they could explain why this strategy was helpful, Why is this strategy useful?, and whether or not they would use this strategy in the future, Evaluating Strategy. I loved watching the second student cross off the minuend, 40,000 and rewriting 39,999 (instead of rewriting the entire problem). After watching how much more efficient he was, I shared his steps with the class. If I had to teach this lesson again, I would model his strategy instead of mine!

Students Following my Model: Student Example A

Different way of Solving: Student Example B

Conferencing: Reflection

# Subtracting from Nines

Unit 5: Adding & Subtracting Large Numbers
Lesson 15 of 16

## Big Idea: Students will subtract from multiples of 10 by changing all the digits into nines.

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2 teachers like this lesson
Standards:
Subject(s):
Math, Number Sense and Operations, subtracting, subtracting from nines
110 minutes

### Kara Nelson

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