How Do Tornadoes Happen

Goal

Students learn how tornadoes form and the atmospheric conditions that are conducive to tornadoes.

Engage students by asking questions.

  • Ask students to recall a tornado they have seen (either on television, movies, or in person). What do they remember? For those who have experienced a tornado in person, what types of feelings are associated with the experience? In small groups, ask students to discuss one or more questions they have about how tornadoes form.
  • Tornado Image Gallery: The images in this presentation can be used in many different ways. Note: Photo credits and captions are included in the notes page of the slideshow
    • Have students write down adjectives as they view images (shapes, colors, backgrounds).
    • Have students write down the similarities and differences in the formation of each tornado. What do they notice in the beginning, middle, and end stages of a tornado? Ask students if they observe the formation of the vortex in the images, especially in the series of tornados.
    • Possible extensions for this resource: Have students sort and group images based on appearance or formation stage. (Read How Tornadoes Form to learn about stages.)

Explore through hands-on tornado activities.

  • Twister in a Jar: This simple model demonstrates how a vortex forms. After students have tried the activity, discuss aspects of the model that are useful in explaining how a tornado forms and aspects that might not be accurate. Remind students that all models are wrong, but some models are useful. Discuss whether this model is useful for explaining how tornadoes form.
  • Make a Tornado!: In this hands-on activity, students model the atmospheric conditions that cause a vortex to form.

Explain how tornadoes form and the types of tornadoes through videos, online reading, and an in-class presentation.

  • Tornadoes - Oh My!: Walk students through this tornado presentation or engage your students to be the presenters having each student present one or two slides.
  • How Tornadoes Form: This short reading provides a step-by-step description of how tornadoes form. Engage students to create trivia questions based on this article that they will ask other students.
  • Tornadoes 101: This National Geographic video (5:31) demonstrates how tornadoes form.
  • The Enhanced Fujita Scale rates the strength of tornadoes in the United States and Canada based on damage caused by wind estimates (not measurements).
  • Tornado Strength: This article provides an overview of the strength of tornadoes.

Elaborate student learning by having them compare and contrast tornadoes.

  • Have students compare and contrast images from the Tornado Image Gallery using the Tornado Compare and Contrast Activity Worksheet or the Advanced Tornado Compare and Contrast Worksheet in which students determine their own criteria for grouping similarities, give each group of criteria a title, and then compare and contrast. After completing the worksheet, have students discuss their results in pairs. Consider putting the pairs in quads to continue the discussion. Ask students: Did they all have the same observations and agree on the same analysis? Probably not! Remind students that scientists go through similar practices of analyzing and interpreting data, constructing explanations, engaging in arguments for evidence (NGSS Practices).

Extend student learning by guiding them to put all of the pieces together.

  • Build It Better: This activity from TeachEngineering has students apply their knowledge of tornadoes and resulting damage as they work in groups to design structures intended to withstand and protect people from extremely high winds

Evaluate student understanding of how tornadoes form.

  • Have students create a PowerPoint or Prezi about how tornadoes form. (Extension: Encourage students to reflect on the science practices that they completed in the compare and contrast elaborate activity for documented evidence of NGSS Practices. Have them explain how they analyzed and interpreted data, constructed explanations, and engaged in arguments for evidence with classmates.) Students answers should refer to models of tornado formation, discussion of the limitations of models, and identification of the stages of tornado formation.
  • Compile the questions students wrote while reading about tornadoes (during "Explain" above). Divide students into small groups and answer the questions. Student answers should demonstrate mastery of the science content.