Adding and Subtracting Integers Using a Number Line

Note: This post refers to class on September 19th, 2017

Learning Opportunity

Page 22 #39-42 (show on number line and write number sentence)

Page 23 #47

Today in Class

Today students were shown this image.

Screen Shot 2017-09-20 at 8.31.32 AM

Students were first asked what they noticed about the image.  Here are some of the responses:

Screen Shot 2017-09-20 at 8.33.14 AM

They were then asked what they wondered about the image.

Screen Shot 2017-09-20 at 8.34.24 AM

After reviewing their responses I read to them the following information:

Screen Shot 2017-09-20 at 8.35.42 AM

We discussed the temperatures and what it must be like to go from two different extreme temperatures.  The students were then shown this image:

Screen Shot 2017-09-20 at 8.37.03 AM

We reviewed that “n” is a variable and it is used to represent a number.  In the first number sentence “n” represents -140.  That makes the number sentence 120 + -140 = -20.  In the second number sentence “n” represents 140.  That would make the second number sentence -20 + 140 = 120.

After discussing number lines and number sentences, students worked in groups on the following problems:

Screen Shot 2017-09-20 at 8.39.53 AM

Here are students showing number lines and number sentences for these problems: