Percent of change: What's the deal?

In this lesson, students calculate percent of change and discuss how percent of change is used in retail careers.

A lesson plan for grade 7 Mathematics

By Debbie Brooks, Peggy Dickey, and Jan Sullivan

Provided by CareerStart

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CareerStart lessons: Grade eight

This collection of lessons aligns the eighth grade curriculum in math, science, English language arts, and social studies with potential career opportunities.

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Related topics

• Learn more about algebra, careers, mathematics, and percent of change.

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Essential question: How can the ability to calculate percent of change be important in retail careers?

Learning outcomes

Students will practice calculating percent of change.

Teacher planning

Materials needed

• Worksheet: “What’s the Deal?” (Includes answer key.)
• Overhead copy of worksheet
• Calculator (One for each student)

Time required for lesson

One class period

Activities

1. Ask students when they were last in a store that was having a sale. What signs did they see? (Students may mention seeing signs that said things like “20% off.”
2. Using the career information below, discuss careers in retail stores with the class.
3. Discuss what determines whether you have a percent increase or a percent decrease in price. (The original is either higher or lower than the new amount.)
4. Tell the students that they are going to be in charge of generating a price sheet that lists mark-ups and sales prices for items that are in a retail store.
5. Place students in groups of no more than three for this activity. Hand out “What’s the Deal?” worksheets and have students work through the information given. (40 minutes)
6. Use the overhead copy of the worksheet to have each group write answers to share with the class. (5 minutes)
7. Discuss with students what other careers might involve finding percent of change. (5 minutes) If students need help brainstorming, you may choose to access the following websites:
   • The Bureau of Labor Statistics’ Occupational Outlook Handbook
   • The Bureau of Labor Statistics’ K-12 career home page
   • CareerOneStop.org

Career information

Some of the information below comes from the Bureau of Labor Statistics’ Occupational Outlook Handbook.

Retail managers

Retail managers supervise salespersons and other store personnel. They are responsible for hiring and training retail employees and oversee the daily operations of a retail store. One of the daily operations is setting prices for the items or the inventory in the store. When an item is purchased, the store must mark-up the item. The mark-up needs to be high enough to bring in income, but low enough so the item will sell. When business becomes slow or items do not sell, stores run sales and discount the sales price. Sales managers must be accurate with the mark-ups and discounts.

Retail stores must have a profit to stay in business. The formula used to determine profit is: Profit = Sales - Expenses. Sales are the money customers pay for items purchased. From these sales, expenses are deducted. Expenses include the cost for items or inventory, rent or mortgages, utilities, salaries for salespersons, salaries for office workers, salaries for custodians, advertising costs, office and cleaning supplies, insurance, payroll taxes, sales tax, shipping costs, and any other expense needed to operate the store. The profit will only come from what is left of the mark-up.

• Education: High school and college-level courses related to business
• Pay: $27,500 - $46,500
• Growth: Slower than average; 4% increase over the next 10 years

Salespersons

Salespersons are responsible for assisting customers in finding items to purchase, ringing up the sales, and bagging purchases. They should always be courteous and helpful to the customer. Salespersons may be responsible for opening and closing the cash register and are expected to maintain accurate accounting of the contents in the cash register.

• Education: No formal education is required
• Pay: $17,000 - $41,500
• Growth: Average growth; 12% increase over the next 10 years