In this lesson, students will work together to determine the definition of desertification and create a chart to explain the causes and effects of desertification in the sub-Saharan Sahel region. Then, students will learn how Africa is responding to desertification with a project called the Great Green Wall and how growing the Great Green Wall has changed life in the Sahel. Based on what they have learned about the causes and effects of desertification, students will write their own tweets to raise awareness about the Great Green Wall initiative. This lesson includes optional modifications for distance learning. Resources for use in Google Classroom are included.
How do interactions between humans and their environment impact both the people and the natural environment of the Sahel? What are the causes and effects of desertification in the Sahel? Why is Africa building a Great Green Wall?"
Using the Think-Pair-Share strategy, students hypothesize about color scale representation on an untitled map. Students learn about the driest place on Earth and about the Sahel region of North Africa.
Remaining with their Think-Pair-Share groups, students compare two maps to define desertification.
Working in groups, students read an article and create a chart explaining the causes and effects of desertification in the Sahel.
Students view the short video "Why Does Africa Want to Build a Great Green Wall?" to determine how Africa is responding to desertification and how both desertification and the Great Green Wall project represent human-environment interactions. Students craft tweets using the Tweet Up strategy to raise awareness of desertification and the Great Green Wall initiative.
The Causes and Effects of Desertification chart from the Explain phase of the lesson and the Tweet Up responses from the Extend phase serve as evaluations. Optionally, students may also participate in a Gallery Walk strategy for additional assessment, during which they determine the relationship between different photos and desertification in the Sahel.
Desertification in the Sahel Lesson Slides (attached)
Desertification Think-Pair-Share handout (attached, one per student)
Causes and Effects of Desertification in the Sahel (Article) (attached, one per student)
Causes and Effects of Desertification in the Sahel (Chart for Students) (attached, one per student)
Causes and Effects of Desertification in the Sahel (Chart for Teachers) (attached)
Video Notes Organizer (attached, one per student)
Tweet Up Template (attached, one per student or one per two students)
Gallery Walk images (attached; optional)
Gallery Walk Journal (attached, one per student; optional)
Use the attached Lesson Slides to guide the lesson. Begin by displaying slide three. Hand each student a copy of the attached Desertification Think-Pair-Share chart. Using the Think-Pair-Share strategy, invite students to create individual hypotheses explaining what they think the various colors on the map might represent, based on their prior knowledge. Students should write their hypotheses in the "Think" column next to question one on the chart. Then, to further develop their hypotheses, ask students to pair up or place students in small groups. Ask students to share their hypotheses with their group, discuss, and come to a consensus about what they think the colors on the map represent. Students should write this consensus in the "Pair" column next to question one in their charts. After students have had time to do so, ask each student group to share their thoughts with the class. Lead a brief class discussion to foster understanding of each hypothesis. Then, ask students to summarize what the colors of the map might represent based on shared knowledge in the "Share" column next to question one.
Once the class discussion has established that the yellow and red areas of the map represent the Earth's driest places, ask students where the most arid place on Earth appears to be. Students should note Northern Africa. Move to slide 4 to read the lesson's essential questions: How do the interaction between humans and their environment impact both the people and the natural environment of the Sahel? What are the causes and effects of desertification in the Sahel? Why is Africa building a Great Green Wall?
To answer these questions, students will learn about an area in Africa called the Sahel, and investigate the interactions between those who live there and their environment.
Move to slide 5, which shows a map of the Sahara Desert and the Sahel region. Use this map to illustrate that the Sahara is the largest desert in the world; in fact, Sahara is the Arabic word for 'desert.' Explain that the Sahel is a semiarid grassland along the Sahara's southern edge. Sahel is the Arabic word for 'border,' as the Sahel region is the border between the Sahara Desert and the savannas to the South.
Move to slide 6 and draw attention to the comparison between two maps: the map of the Sahel area on the left, and the "Vulnerability to Desertification" map on the right. Invite students to use these maps to hypothesize on what the term "desertification" might mean. Ask students to examine these two maps to determine what the term "desertification" might mean. Consider pointing out to students the title of the "Vulnerability to Desertification" map, and discussing with students the meaning of the word "vulnerability" (being at risk for harm, exposed to harm, or endangered). Ask students what they think the title of the second map, "Vulnerability to Desertification," means. Let the class discussion come to the conclusion that the map shows areas that are at risk of desertification. Next, ask students, given the two maps, what the relationship is between the Sahel and the concept of "desertification."
Ask students, given the class discussion so far, what the term "desertification" might mean. Students should record their individual hypothesis in the "Think" column next to question two in their Desertification Think-Pair-Share charts. Next, ask students to share their thoughts with their partners or groups. Allow time for each group to come to a consensus and record their answers in the "Pair" column of the chart next to question two. When ready, ask groups to share out their thoughts with the whole class. Students should summarize responses from the class in the "Share" column of the chart of the second question.
Show slide 7 and discuss the definition of desertification: desertification is the process by which land becomes more and more dry until it turns into desert. This is an advanced form of land degradation. Consider explaining to students that land degradation includes the deterioration or depletion of the soil, hence its inability to support vegetation. Ask students to record this definition in the bottom row of the Desertification Think-Pair-Share chart for reference during the rest of the lesson. Now that students have learned about desertification, the next activity will involve learning about the causes and effects of desertification in the Sahel.
Hand each student a copy of the attached Causes and Effects of Desertification in the Sahel (Article) reading. Working in their groups, students should use the Categorical Highlighting strategy to highlight causes of desertification in one color and the effects of desertification in a different color. If highlighters are not available, students can circle causes and underline effects. Remind students that the causes of desertification are the things that contribute to making desertification happen. Effects of desertification are the things that occur as a result of desertification.
Allow enough time for students to read and highlight. Once finished, pass out a copy of the attached Causes and Effects of Desertification in the Sahel (Chart for Students). Ask students to work with their groups to fill in the "Causes of Desertification" column with three to four causes of desertification found in the article, with a correlating effect in the "Effects of Desertification" column. Ask students to include a 1–2 sentence summary explaining each cause and effect they list.
Once this is finished, ask for volunteers from each group to share out answers, add missing information, and clarify any misconceptions.
Now that students have learned about the causes and effects of desertification, introduce the next activity, which involves learning about what steps are being taken in the Sahel to prevent it. Move to slide 8 to show a visual of this effort, called the Great Green Wall.
Explain to students that the Great Green Wall was a project started in 2007 to combat the desertification of the Sahel. Consider visiting the Great Green Wall website for more information about this project to share with the class, or having students do so if time permits.
Pass out a copy of the attached Video Notes Organizer to each student, or ask students to use notebook paper to take notes. Move to slide 9, which features an introductory video about the Great Green Wall. Ask students to take notes on their organizer as they watch, answering the question on the hand out: Why is Africa building a Great Green Wall?
Play the video by clicking the link on the slide (or this link) or using the embedded version of the video below. Consider showing the video more than once if it would help students take notes. As an alternative, if students have access to their own device, they may view the video again on their own or in small groups.
Once students have finished taking notes, ask them to share some of their takeaways with their groups. Then, ask for volunteers to share some of their answers with the class.
Additionally, explain to students that, since its inception, the Great Green Wall initiative has evolved from simply planting a wall of trees to supporting a myriad of conservation strategies. This means planting more sustainable crops rather than cash crops, crop rotation methods, sustainable irrigation practices, grazing rotation methods, etc.
Another important aspect of the Great Green Wall project is raising public awareness. For the next activity, explain to students that the United Nations Convention to Combat Desertification has launched a public awareness campaign on the Great Green Wall, called "Growing a Public Wonder." This campaign aims to boost global awareness of the initiative in public spheres, policy debates, media, and cultural sectors, meant to inspire long-term public and private investment in the initiative. With this in mind, hand each student a copy of the attached Tweet Up Templates and move to slide 10. Invite students to write a tweet about the Great Green Wall using the Tweet Up strategy. Students should keep in mind the global awareness initiative and how they can inform the public about the causes and effects of desertification, and how the Great Green Wall combats it.
Students' Causes and Effects of Desertification charts and Tweet Up responses can be used as assessments for this lesson. Additionally, see the optional assessment below featuring the Gallery Walk strategy. This optional assessment involves students participating in a gallery walk to view pictures related to desertification in the Sahel and explain the details of these relationships in their own words.
Pass out a copy of the attached Gallery Walk Journal to each student. To start the gallery walk, divide students into groups based on the number of photos hanging in the room. There should be one group starting at each photo. Give students three minutes at each photo to record in their journals how the photo relates to desertification in the Sahel. After one complete round has been made, and every group has visited every gallery photo, have groups return to their first photo. Ask a representative from each group explain how their photo is related to desertification in the Sahel with the class. Students can turn in their charts as a summative assessment.
BBC News. (2017, September 26). Why is africa building a great green wall? BBC News. Retrieved November 25, 2019, from https://www.youtube.com/watch?v=4xls7K_xFBQ
Great Green Wall. (n.d.). Retrieved from https://www.greatgreenwall.org
Great Green Wall. (n.d.). Growing a world wonder. Retrieved from https://www.greatgreenwall.org/about-great-green-wall
K20 Center. (n.d.). Categorical highlighting. Strategies. Retrieved from https://learn.k20center.ou.edu/strategy/fc74060730ea745c8c4f356aa204c85d
K20 Center. (n.d.). Gallery walk / carousel. Strategies. Retrieved from https://learn.k20center.ou.edu/strategy/d9908066f654727934df7bf4f505a54d
K20 Center. (n.d.). Think-pair-share. Strategies. Retrieved from https://learn.k20center.ou.edu/strategy/d9908066f654727934df7bf4f5064b49
K20 Center. (n.d.). Tweet up. Strategies. Retrieved from https://learn.k20center.ou.edu/strategy/d9908066f654727934df7bf4f505fb94
United Nations Convention to Combat Desertification. (n.d.). The great green wall initiative. Retrieved from https://www.unccd.int/actions/great-green-wall-initiative