Lesson Plan Title : Percentages

Age Range:

Grade 9 through Grade 12 (High School)

Overview and Purpose:

Students will be able to apply percentages to real life situations by figuring the amount of income tax that will be withheld from a salary. Students will learn about credit and credit scores. They will learn what will impact their scores and what will help their scores. Make sure the students will learn about all the aspects of credit, and that they will be able to make informed decision regarding credit.


The student will be able to

*calculate how much they will pay in federal, state, and local income tax for a year when they are paid for doing their dream job.

*Research salary information on the Internet.

Students will understand the concept of credit
They will understand the concepts of a credit score.
They will learn the importance of having good credit.
Concept of interest, and learn how to analyze interest.


Internet access

Tax percentages for your area

Math journals

Calculators (optional)


1. Open by asking if any of the students have a credit card. If not ask if their parents have credit cards, and if they understand how they work.
2. Next write these words on the board: Credit, credit card, credit risk, interest, APR, and credit limit. Make sure I discuss this with the class in detail.
3. Explain how credit cards work. Explain to them how the interest works if they do not pay off the balance of the card when it is due.
4. Discuss the difference between credit cards, debit cards, and cash. Explain how each of them work.
5. Ask how banks make decisions on if they want to offer you credit.

Begin a discussion about credit scores, how lenders use them, and what makes up an individual's credit score. Explain that a credit score is a number calculated using a number of different variables. The resulting score helps lenders determine how likely a borrower is to pay a loan or credit card back on time. In other words, a score is a snapshot of "credit risk" at a given time.

Ask students if they know which organizations calculate credit scores: is it the banks, the government, or private organizations? (Answer: Private organizations calculate credit scores. One well-known organization is the Fair Isaac Corporation, which produces the "FICO score" -- the most widely used credit score. Other scores include NextGen, VantageScore, and the CE Score.)

Have students look up the average salary for their dream job. Explain that they will have to pay taxes on that salary to the local, state and federal government. They can either research the tax percentages or you can give them to them. Have them calculate how much each week, month, and year they will pay in taxes and record the amount in their journals.

Graph the different amounts and have them draw conclusions about the amount of taxes people pay.


Homework could include having students calculate and graph the amount paid in taxes for salaries at least $25,000 apart. More advanced students may also want to research the amount of other taxes withheld (Social Security, Workman's Compensation) and analyze how that affects salaries.