⛓️ Food Chains: Who Eats Who?

Grade 2 Life Science, Unit 2 — Lesson 3

📚 Grade: 2nd Grade ⏱️ Duration: 45 minutes 🔬 Subject: Life Science — Ecosystems 🌱 Unit: 2-LS2 Ecosystems
☀️🌿🦗🐸🦅
Energy flows from the sun, through plants, through animals — and back to the soil.
📋 NGSS Standard:
2-LS2-1 — Make observations of plants and animals to compare the diversity of life in different habitats.

🎯 Learning Goals

📦 Materials

🏠 What You Need

✅ All household items — no specialty purchases needed!

📖 Vocabulary

Food Chain A line showing what eats what, from plants to animals
Producer A plant that makes its own food from sunlight — it "produces" energy
Consumer An animal that eats other living things to get energy
Decomposer A living thing (like a worm or fungus) that breaks down dead plants and animals
Herbivore An animal that only eats plants
Carnivore An animal that eats other animals

🌍 Background

Every animal in an ecosystem needs energy to live. That energy originally comes from the sun. Plants capture sunlight and turn it into food through photosynthesis — this makes plants "producers" because they produce energy from sunlight. Animals that eat plants are called herbivores, and they get the plant's stored energy when they eat.

A food chain shows how energy flows from one living thing to the next. A simple food chain might look like this: Sun gives energy to Grass. Grass feeds the Grasshopper. Grasshopper feeds the Frog. Frog feeds the Hawk. Every link in the chain matters — remove one and the whole chain is affected.

When plants and animals die, decomposers like earthworms, fungi, and bacteria break them down. They return nutrients to the soil, which helps new plants grow. Decomposers are the cleanup crew of the ecosystem. Without them, dead things would pile up and plants would run out of nutrients. They complete the cycle and keep the ecosystem healthy.

☀️ Sun → 🌿 Grass → 🦗 Grasshopper → 🐸 Frog → 🦅 Hawk → 🪱 Worm (decomposes)
Energy source
Producer
Herbivore / Consumer
Carnivore / Consumer
Carnivore / Consumer

🔬 Activity: Food Chain Mobile

Step 1: Cut or tear 6 strips of paper (about 1 inch wide and 5 inches long).
Step 2: On each strip, write and draw one of these: SUN ☀️, GRASS 🌿, GRASSHOPPER 🦗, FROG 🐸, HAWK 🦅, WORM 🪱
Step 3: Shape each strip into a loop and connect them like a paper chain, in this order from top to bottom: SUN — GRASS — GRASSHOPPER — FROG — HAWK — WORM.
Step 4: Between each link, you can write a tiny label: "gives energy to" or "is eaten by" — or just let the chain show the order.
Step 5: Punch or cut a small hole at the top of the SUN strip and tie a string through it. Hang your Food Chain Mobile from a doorway or window!
Step 6: Look at your finished mobile and discuss: Where does the energy START? (The sun.) Where does it END? (Back in the soil, thanks to the worm!) Now try removing one link — what happens to all the other links?

💬 Discussion Questions

🗣️ Question 1: What would happen to the food chain if all the grasshoppers suddenly disappeared?

Suggested answer: The frogs would lose their main food source and their population would shrink. With fewer frogs, the hawk population would also shrink from lack of food. Meanwhile, the grass would grow unchecked with no grasshoppers eating it — it might take over. Scientists call this a "trophic cascade." Removing one species affects every other species in the chain, both above and below it.

🗣️ Question 2: Why are decomposers important even though we rarely notice them?

Suggested answer: Decomposers are the most important recyclers on Earth. They break down dead leaves, dead animals, and waste, releasing nutrients back into the soil. Without them, nutrients would stay locked inside dead things and plants would not be able to grow. Earthworms, fungi (mushrooms), and bacteria are all decomposers. They are working constantly — just underground and out of sight.

🗣️ Question 3: The food chain starts with the sun. What would happen to all food chains if the sun disappeared?

Suggested answer: All food chains would collapse. Without sunlight, plants could not photosynthesize and would die. Without plants, herbivores would die. Without herbivores, carnivores would die. Every food chain on Earth starts with the sun — it is the ultimate source of all energy for life on our planet.

⛓️ Student Worksheet — Food Chains

Name: ________________________________      Date: ________________

Part 1 — Label the Food Chain

Write the name of each living thing in the box. Then write "Producer," "Herbivore," or "Carnivore" on the line below each animal.

☀️ Sun 🌿 Grass 🦗 Grasshopper 🐸 Frog 🦅 Hawk
Energy source

Part 2 — Fill in the Blanks

A makes its own food from sunlight.
A eats only plants.
A eats other animals.
A breaks down dead things and returns nutrients to the soil.

Part 3 — Draw Your Own Food Chain

Think of animals in your backyard or neighborhood. Draw a food chain with 4 links. Include arrows showing the direction energy flows.

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Part 4 — Think About It

If I removed the FROG from the food chain, I think this would happen:

👩‍🏫 Parent/Teacher Notes