Lesson 3 Create and Use a Ruler
Let’s create rulers and use them to measure and compare lengths in centimeters.
Warm-up Number Talk: Subtract Two Digits
Find the value of each expression mentally.
Activity 1 Create a Ruler
Use your tools to make a ruler that shows lengths in centimeters.
Compare your ruler with your partner’s ruler.
Activity 2 Measure and Compare Lengths
Use your ruler to measure the length of each rectangle. Don’t forget to label your measurements.
How many centimeters longer is rectangle a than rectangle b?
How many centimeters longer is rectangle f than rectangle d?
Which two rectangles are the longest? How long would the rectangle be if you joined them together?
How many centimeters long is each side of the triangle? Label each side.