Last updated: July 10, 2019
Lesson Plan
Understanding Percent Using Buffelgrass
- Grade Level:
- Middle School: Sixth Grade through Eighth Grade
- Subject:
- Math
- Lesson Duration:
- 60 Minutes
Objective
The objective of this lesson is to help students learn and understand percentages while also learning about the significance of buffelgrass, an invasive plant in the Sonoran Desert.
Background
Plants and animals that are brought from one part of the world to another, and then grow wild, are called invasives. Invasive plants can affect native plants and wildlife, cause fires, endanger the ecosystem, and make the beautiful landscape around Tucson less attractive for visitors.
Whether they arrived accidentally in trucks or trains, or are planted intentionally for soil conservation or other reasons, invasive plants are a threat to the saguaro cactus and the other interesting cacti and plants of Saguaro National Park and the Sonoran Desert.
Buffelgrass (Pennisetum ciliare), called the "archenemy of the Sonoran Desert," is an invasive grass that is causing significant damage to the native ecosystem. Buffelgrass is native to Africa and the Middle East. It causes fires that kill saguaros, and compete with native plants for precious desert water.
Preparation
Familiarize yourself on buffelgrass. Be able to talk about its origin and what it is briefly in class.
Print Buffelgrass Percent Worksheet
Materials
Download Buffelgrass Percent Worksheet
Procedure
#1: As a class, watch the video on buffelgrass. After, talk to students about the role it plays on the Sonoran Desert.
#2: Introduce the concept of percentages to students. Ask, what is percent? Where do they see percent being used in real life?
#3: Before starting the worksheet, make sure that the students are comfortable with converting decimal and fraction into percent and vice versa. Review with students the steps in percent conversion. If starting with a decimal, one can multiply the number by 100. Then, place the % symbol to the right of the product. Another way to convert a decimal to percent is by moving the decimal point two places to the right and then putting the % symbol after. If starting with a fraction, make sure that it is first converted to an improper fraction. Then, divide the numerator from the denominator. Lastly, multiply the quotient by 100 and place the % symbol next to the product.
#4: Let the students work on the Buffelgrass Percent worksheet.
#5: Come together as a class and check answers.
Vocabulary
Buffelgrass- an invasive species not native to the Sonoran Desert
Percent- parts per hundred
Rubric/Answer Key
Buffelgrass Percent Answer Key