Lesson Plan: Percents and Measurement

This comprehensive lesson plan is designed to introduce sixth-grade students to the concept of percents, emphasizing their relationship to fractions and decimals. Through engaging activities, detailed examples, and practical applications, students will develop a strong foundation in interpreting and solving percent problems in various real-world contexts.

Lesson Objectives

• Define percents and understand their connection to fractions and decimals.
• Convert between fractions, decimals, and percents.
• Solve problems involving finding the percent of a number, determining what percent one number is of another, and finding the whole given a part and a percent.
• Apply percent concepts to real-world scenarios, including calculating discounts, tax, percent increase/decrease, and simple interest.

Key Vocabulary

• Percent: A ratio that compares a number to 100, denoted by the symbol '%'. For example, 45% equals 45 out of 100, or 45/100.
• Percentage: The result obtained by multiplying a quantity by a percent. For instance, in calculating 20% of 50, the number 10 is the percentage.
• Proportion: An equation that states two ratios are equal, often used to solve percent problems.
• Percent Increase: The amount a value has grown, expressed as a percentage of the original value.
• Percent Decrease: The amount a value has reduced, expressed as a percentage of the original value.
• Simple Interest: Interest calculated on the principal amount only, using the formula $I = P \times r \times t$, where $I$ is interest, $P$ is principal, $r$ is the annual interest rate, and $t$ is time in years.

Warm-Up Activities

1. Review of Fractions and Decimals: Discuss how fractions and decimals are related, and demonstrate converting between them. Highlight that percents are another way to represent these values, specifically as parts per hundred.
2. Visualizing Percents: Use a 10x10 grid to shade various percentages, helping students visualize what different percents represent. For example, shading 25 squares illustrates 25%.

Teaching Examples

1. Finding a Percent of a Number: Calculate the sale price of an item after a 25% discount.
2. Determining What Percent One Number Is of Another: Find out what percent 18 is of 24.
3. Finding the Whole Given a Part and a Percent: Determine the original price of an item if 20% off equals $12.
4. Calculating Percent Increase: Compute the new salary after a 15% raise on a $50,000 salary.
5. Calculating Percent Decrease: Determine the decreased population of a town after a 10% decline from 5,000 residents.
6. Understanding Simple Interest: Calculate the interest earned on a $1,500 investment at a 4% annual interest rate over 3 years.

Review Section

1. Lesson Summary: Recap the key concepts covered, emphasizing the importance of understanding percents and their applications in everyday situations.
2. Key Vocabulary Review: Reinforce the definitions and applications of essential terms related to percents.
3. Additional Worked-Out Examples: Provide practice problems that mirror real-world scenarios, such as calculating tax on a purchase, determining the percent decrease in price during a sale, and computing simple interest earned over time, to solidify students' understanding and problem-solving skills.

Subscribers to Media4Math can download this lesson plan in PDF format for easy classroom use.