Lesson: Stopping the Sahara

Play the video “The Effects of Climate Change” and/or “The Great Green Wall.” Then, before or after reading the article, spark a discussion based on the following questions:

• What are the characteristics of a desert?
• How do trees and other plants help the environment?
• Why might farmers divide their lands into different areas or sections?

• Have students draw a square and divide it into 3 equal sections.
  
• Describe how you split your square. (Answers will vary but students should have divided their squares by drawing
  2 horizontal lines or 2 vertical lines that are the same distance apart.)
• How many parts make up your whole square? (3) Three represents your denominator, or number of parts in your whole.
• Draw a star on 2 of your parts. How many parts of your square have a star? (2 parts) This is your numerator.
• What fraction of your square has stars? ( ²/₃ )
• Play the instructional video “Fractions.”

• Where did the denominator of 4 come from? (The number of equal parts the land is divided into.)
• What does each part of land represent? ( ¹/₄ )
• If the plot of land were shaped like a square instead of a rectangle, would the fraction have changed? (No, there would still be ³/₄ of the land used for trees.)
• What fraction of the land will be used for farming? ( ¹/₄ )

Have students complete problems 1 through 4 on page 5 of the article.

Skills Sheets: Level Down: Equal Shares (2.G.A.3; 2.3A) | On Level: DynaDash: Partitioning Shapes (3.NF.A.1; 3.3E) |Level Up: Parallel and Perpendicular Lines (4.G.A.2; 4.6A)

SEL (Social-emotional learning activity/prompt): Many people around the world are working together to help slow climate change. Have students think about something they can do for their community or around their home to help make the planet a healthier place.

Dynamath@Home: Have students use a flat circular, square, or rectangular object (such as a paper plate or napkin) and fold it into 8 equal sections. Open it and trace the folds to make a grid. Then have students collect a handful of small items (paper clips, beads, etc.) and drop the items onto the center of their grid so they scatter over it. Ask them to write fractions representing how many parts have or do not have the different items on the grid.