poem "Smart" by Shel Siverstein from Where the Sidewalk Ends
Ratios, rates and unit rates
Lesson Created by:
Marie Green, Susan B. Anthony Middle School, Manhattan, KS.
- The poem "Smart" from the Book - Where the Sidewalk Ends, by Shel Silverstein, 3 x 5 note cards
1. Launching the lesson (engage):
- Read the poem "Smart"
- Discuss why the boy was confused. He traded his dollar for 2 quarters because 2>1. Why is this a problem?
2. Developing the lesson
- Have students fill out the note card. On it two numbers have been written. The student is to show a relationship between the two numbers (Ex. 5,50). A possible answer is 5 dimes to 50 cents. Have the students share the relationships they have written.
- Now introduce the terms: rate-ratio of two measurements with different units ratio- comparison of two numbers by division
- Each student is to tell whether he has written a rate or a ratio.
- On the back of the note card each student is to write his own set of numbers and share a relationship that he has made.
- Discuss the student-made relationships.
- Once again discuss the relationships as either a rate or a ratio
- Introduce the idea of unit rate. Unit rate - a rate with a denominator of 1
- Have each student change the numbers on their card to a unit rate.
- Pose the question: What kind of unit rate would the smartest son need to make sure he wasn't being cheated? (1: 1)
- Why do we simplify ratios? (To have simpler numbers to work with)
- Students are to complete the worksheet E-8 on ratio and unit rate.