Money Math · Lesson Plan

Calculating the Amount of a Discount

Discounts are everywhere when you shop, and figuring the dollars off is just finding the percent of a number. This lesson teaches the ‘of means multiply’ key-word method: convert the percent to a decimal and multiply it by the price to get the amount of the discount. Students practice on twelve problems (answer key included).

Grades 6–9 Lesson Plan 30–45 minutes Free Lesson Plan Lesson & Worksheet: Full Membership

Calculating the amount of a discount lesson illustration

For Teachers

Lesson at a glance

Topic: Money Math
Grade Level: Grades 6–9
Resource Type: Lesson + Worksheet
Estimated Time: 30–45 minutes
Format: Lesson + worksheet + answer key
Materials: Printable lesson, worksheet, answer key, calculator

What Students Learn

Learning objectives

Explain that finding a discount means finding the percent of a number
Use the ‘of means multiply’ key word to set up an equation
Convert a percent to a decimal
Calculate the dollar amount of a discount
Distinguish the discount amount from the sale price

Materials

What you’ll need

Printed copies of the lesson and worksheet (one per student)
Calculators
Pencils
Whiteboard or projector for worked examples

Key Terms

Vocabulary

Discount: An amount taken off the original price.
Percent of a number: A part of a number found by multiplying.
Decimal: A percent rewritten for multiplying (e.g., 15% = .15).
Original price: The price before any discount.
Amount of the discount: The dollars taken off — not the sale price.
Of: A key word meaning multiply.

For Teachers

Lesson plan

Estimated time: one 30–45 minute class period.

Lesson sequence

Introduction (5 min). Pose “What is 15% of $35.00?” and connect it to a store discount.
Teach the method (12 min). Use the ‘of means multiply’ key word, convert the percent to a decimal, and multiply. Stress that this is the discount amount, not the final price.
Worksheet (15 min). Students find the amount of twelve discounts.
Review (8 min). Check answers with the key.

Assessment

Assess the completed worksheet against the included answer key.

Discussion

Discussion questions

Why does ‘of’ tell you to multiply?
Why do you convert the percent to a decimal first?
What’s the difference between the amount of a discount and the sale price?
Where do you see percent discounts in real life?
How would a bigger percent change the amount taken off?

Printable Lesson, Worksheet & Answer Key