Science lesson plan · 6th grade (Year 7 in England) · 30 minutes
Food webs and interdependence
Ecosystems and food chains
CCSS NGSS.MS-LS2-1CCSS NGSS.MS-LS2-2CCSS NGSS.MS-LS2-4England: KS3 Biology: Interactions and interdependenciesEngland: KS4 Combined Science: Ecosystems
Objective and success criteria
Students will: Food webs and interdependence.
- I can answer questions on today's skill on my own, without help.
- I can explain each step and say why it works.
- I can check my answer and spot a mistake.
Before and after
Needs first: Producers, consumers, predators and prey
Leads to: Energy transfer and pyramids; Sampling with quadrats; Biodiversity under pressure and how we protect it
Materials: Food web cards, Arrows to build chains, Mini whiteboards, A diagram or short video clip of the idea, Printed student sheet (below).
Warm-up · 4 min
- Quick retrieval from earlier learning (Producers, consumers, predators and prey). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- grass → grasshopper → frog → snake What is the frog in this food chain? (secondary consumer / tertiary consumer / primary consumer / producer) → secondary consumerPrompt: Start at the plant and count the arrows.
- seeds → mouse → owl Which animal is the predator of the mouse? (owl / seeds / mouse) → owlPrompt: A predator hunts and eats other animals; its prey is the animal it eats.
- Food chains: which statement is true? (A consumer gets its energy by eating other living things. / Herbivores are predators. / A food chain can start with a lion. / Producers eat consumers.) → A consumer gets its energy by eating other living things.Prompt: Producers make food; consumers eat.
Hook · 3 min
- Show a food web and ask what would happen if one animal disappeared.
- Share the objective: Food webs and interdependence. Read the success criteria together.
I do: model it · 7 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: Pond food web: algae are eaten by tadpoles and water fleas. Tadpoles and water fleas are eaten by small fish. Small fish are eaten by herons. If the small fish died, what would happen to the herons?
- Step 1: Herons lose their food source, so their numbers fall.
- Step 2: So the answer is: They would decrease or move away
- Answer: They would decrease or move away
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 6 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- Pond food web: algae are eaten by tadpoles and water fleas. Tadpoles and water fleas are eaten by small fish. Small fish are eaten by herons. If all the small fish died, what would probably happen to the tadpoles at first? (They would increase / They would stay exactly the same / They would turn into fish / They would decrease) → They would increasePrompt: What eats tadpoles?
- What does "interdependence" mean in an ecosystem? (Living things depend on each other, so a change to one affects others / Every animal lives alone / Plants do not need animals at all / Only predators matter) → Living things depend on each other, so a change to one affects othersPrompt: Think of bees and flowers.
You do: independent practice · 7 min
- Students work on the student sheet. Circulate and check the first two answers of every student early.
- Students who finish: write a question of their own for a partner, with the answer.
The 6 questions are on the student sheet below, with answers in the key.
Exit ticket · 3 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- Pond food web: algae are eaten by tadpoles and water fleas. Tadpoles and water fleas are eaten by small fish. Small fish are eaten by herons. If the small fish died, what would happen to the herons? (They would decrease or move away / They would eat algae / They would increase / Nothing) → They would decrease or move awayPrompt: What do herons eat in this web?
- Why is a food web more realistic than a single food chain? (Animals only ever eat one food / Most animals eat, and are eaten by, more than one kind of living thing / Food webs only show plants / Food webs have no producers) → Most animals eat, and are eaten by, more than one kind of living thingPrompt: Does a fox eat only rabbits?
Watch out for
- Everyday meanings of words getting in the way of the science meaning: define key words explicitly.
- Remembering facts without the reason: ask "why?" and "what is the evidence?"
Support and stretch
Support
- Review first: Producers, consumers, predators and prey.
- Use concrete materials: food web cards.
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- Move on to: Energy transfer and pyramids; Sampling with quadrats; Biodiversity under pressure and how we protect it.
- Explain a common mistake in writing and how to fix it.
- Write a word problem that uses today's skill, then solve a partner's.
Homework and more practice
Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-6.
Free lesson plan from eurekami.com/lesson-plan-builder