You can print this activity, or assign it through a digital classroom!

###The challenge

High above the Sonoran Desert, a red-tailed hawk glides through the air. The hawk searches the ground below for its next meal.

The desert stretches for miles. It is covered with cactus plants, brittlebush, and mesquite trees. Below the hawk, insects and small animals move from one shady spot to another. They are also searching for food.

Where does the energy come from that keeps all these desert organisms alive—especially a carnivore, such as the red-tailed hawk?

In this activity, students use a deck of cards to explore how energy moves from one organism to another in a desert ecosystem. Students begin with plants that capture energy from sunlight to make food. Then, they follow that energy as it goes from plants to the animals that eat them. Finally, students figure out how much energy it takes to feed a carnivore at the top of the food chain.

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###Overview

This activity is designed to be completed in 60-70 minutes, with optional time for follow-up creative projects. We've organized the activity into short sections, allowing you to easily adapt it to your class schedule.

  • Setting the stage—Students review key ideas about energy and food chains. They build a simple food chain model and identify producers, herbivores, omnivores, and predators. (15 minutes)
  • Part 1: Play the Food Chain Game—Students play the Food Chain Game to model how energy moves from producers to consumers. Students work in pairs and record their actions in a data table. (30 minutes)
  • Part 2: Explore your game data—Students use their game data to answer questions about energy flow, food chains, and why carnivores require large amounts of energy to survive. (15 minutes)
  • Keep creating!—Students apply their learning by changing existing rules or adding new rules to the Food Chain Game. They explain how these changes affect energy flow in the game and what that might represent in a real ecosystem. (10 minutes)
  • More creative activities!—Students can choose from additional project ideas. Each project encourages students to combine scientific knowledge with creativity to produce something new.

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###Related Khan Academy content

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