## Reflection: Developing a Conceptual Understanding Using Mental Math to Add and Subtract - Section 1: Opener

The lesson made the students really think.  It is hard for some students to work on a skill without writing it down.  I feel that if the students can do it in their heads, then it will make it easier for them to work problems with pencil and paper.

My rationale for not letting them use pencil and paper at all was because I felt like it gave the lesson a twist.  It gained the students attention.  It turned the lesson into a challenge.  I know that mental math means doing it in your head, but it could have easily been done with paper and pencil.  It would have been easier for me to see how the students were thinking if I had them put it down on paper.  I chose not to do this.

From their oral responses and dry erase board response, I gained enough insight on the students' level of understanding.

Mental Math
Developing a Conceptual Understanding: Mental Math

# Using Mental Math to Add and Subtract

Unit 11: Adding and Subtracting Whole Numbers
Lesson 1 of 11

## Big Idea: Students can use the break apart, compensation, and counting on methods to add and subtract without paper and pencil.

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10 teachers like this lesson
Standards:
Subject(s):
Math, Number Sense and Operations, add and subtract whole numbers, Operations
60 minutes

### Rose Monroe

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