• Quick retrieval from earlier learning (Food webs and interdependence). Students answer on mini whiteboards.
• Show answers together and note who needs support in the main task.

1. 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 decrease / They would stay exactly the same / They would turn into fish / They would increase) → They would increasePrompt: What eats tadpoles?
2. Bees are declining. Why could this affect fruit farmers? (Bees make the rain / Bees eat fruit / Fewer flowers would be pollinated, so less fruit forms / Fruit trees need honey to grow) → Fewer flowers would be pollinated, so less fruit formsPrompt: What do bees carry between flowers?
3. Food webs: which statement is NOT true? (Predator and prey populations often rise and fall in cycles. / Plants compete for light, water and minerals. / Animals often compete for food, water and space. / Plants do not compete with each other.) → Plants do not compete with each other.Prompt: Think about what happens when one population changes.

• Show a food web and ask what would happen if one animal disappeared.
• Share the objective: Biodiversity under pressure and how we protect it. Read the success criteria together.

• Work through the example out loud, saying why you do each step, not just what you do.
• Example: A survey found 200 breeding pairs of a bird species in 2010 and 180 in 2024. What was the percentage decrease?
• Step 1: 200 − 180 = 20
• Step 2: 20 ÷ 200 × 100 = 10
• Step 3: So the answer is: 10 %
• Answer: 10 %
• Pause after each step and ask a student to say what comes next.

• Do these together. Students try each step on whiteboards before you reveal it.
• Use the hints as prompts rather than giving the answer.

1. A survey found 200 hectares of rainforest in 2010 and 170 in 2024. What was the percentage decrease? → 15 %Prompt: Find the decrease first.
2. Which action helps increase biodiversity on farmland? (removing all hedges / growing one crop everywhere / spraying more insecticide / planting hedgerows and leaving wildflower field margins) → planting hedgerows and leaving wildflower field marginsPrompt: Wildlife needs food and shelter.

• 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 8 questions are on the student sheet below, with answers in the key.

• Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.

1. Biodiversity: which statement is NOT true? (Landfill sites increase the space for wildlife. / Global warming is changing where some species can live. / Breeding programmes can help protect endangered species. / Fertiliser running into lakes can cause algae to grow and oxygen to fall.) → Landfill sites increase the space for wildlife.Prompt: What does biodiversity actually measure?
2. Which action helps increase biodiversity on farmland? (planting hedgerows and leaving wildflower field margins / growing one crop everywhere / removing all hedges / spraying more insecticide) → planting hedgerows and leaving wildflower field marginsPrompt: Wildlife needs food and shelter.

Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-10.