• 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. Woodland food web: grass is eaten by rabbits and mice. Seeds are eaten by mice. Rabbits are eaten by foxes. Mice are eaten by foxes and owls. Which animal is eaten by two different predators? (foxes / owls / rabbits / mice) → micePrompt: Look for an animal that both foxes and owls eat.
2. Why is a food web more realistic than a single food chain? (Food webs only show plants / Animals only ever eat one food / Food webs have no producers / Most animals eat, and are eaten by, more than one kind of living thing) → Most animals eat, and are eaten by, more than one kind of living thingPrompt: Does a fox eat only rabbits?
3. Food webs: which statement is NOT true? (Plants compete for light, water and minerals. / Animals often compete for food, water and space. / Predator and prey populations often rise and fall in cycles. / 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: Sampling with quadrats. Read the success criteria together.

• Work through the example out loud, saying why you do each step, not just what you do.
• Example: Five 1 m² quadrats contained these numbers of daisies: 7, 4, 11, 4, 10. What is the mean number of daisies per quadrat?
• Step 1: (7 + 4 + 11 + 4 + 10) ÷ 5 = 7.2
• Step 2: So the answer is: 7.2
• Answer: 7.2
• 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. Five 1 m² quadrats contained these numbers of daisies: 10, 5, 6, 11, 9. What is the mean number of daisies per quadrat? → 8.2Prompt: Add up all the counts.
2. The mean number of buttercups in a 1 m² quadrat is 9. The field is 50 m². Estimate the number of buttercups in the field. → 450Prompt: How many quadrats would fit in the field?

• 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. Five 1 m² quadrats contained these numbers of daisies: 5, 7, 3, 2, 11. What is the mean number of daisies per quadrat? → 5.6Prompt: Add up all the counts.
2. The mean number of buttercups in a 0.25 m² quadrat is 11. The field is 50 m². Estimate the number of buttercups in the field. → 2200Prompt: How many quadrats would fit in the field?

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