Twenty-five percent off. Buy one get one free. $2.99 a piece but only if you buy three or more. It’s no secret to us as adults that sellers aren’t always upfront about what something actually costs, but it can come as a surprise to students. This “Finding the Better Buy” lesson for grades 6-8 covers tons of that content in a fun and relevant way. It’s all part of our Adventures in Math resource center!
What’s in the “Finding the Better Buy” lesson?
This lesson is divided into three parts, and each one corresponds with a section of the “Road Map to the Better Buy” activity sheet:
Part 1—Saving Money by Finding the Better Buy: Walk students through the process of finding the individual unit price using funny examples (horseradish-flavored gummy slugs, anyone?).
Part 2—Saving Money With Discounts: This section is all about sales. Work with your students on “percentage off” problems.
Part 3—Taking Fixed and Variable Costs into Account to Determine the Better Buy: It’s not always a straightforward calculation! This section introduces the idea of fixed and variable costs in more complicated (and realistic!) scenarios.
Standards
- Develop an understanding of personal financial literacy, including evaluating purchase options involving discounts, unit costs, and fixed/variable costs, to determine the better buy.
- Develop an economic way of thinking and problem-solving as a consumer.
- Solve problems using the four operations with whole numbers and decimals to hundredths.
- Use positive and negative numbers to represent quantities in real-world contexts.
- Solve problems involving rates and percentages, including multi-step problems that use percent increase and percent decrease, and financial literacy problems.
