• 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? (owls / foxes / rabbits / mice) → micePrompt: Look for an animal that both foxes and owls eat.
2. Rabbits and sheep both eat grass in the same field. This is an example of… (predation / competition / photosynthesis / decomposition) → competitionPrompt: They both want the same limited resource.
3. Food webs: which statement is NOT true? (Plants compete for light, water and minerals. / Removing one species can affect many others in a food web. / A food web contains only one food chain. / Predator and prey populations often rise and fall in cycles.) → A food web contains only one food chain.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: 11, 9, 5, 8, 8. 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 14. The field is 1000 m². Estimate the number of buttercups in the field. → 14000Prompt: 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. How can you see how plant species change from a hedge to the middle of a field? (Count only the tallest plants / Sample at night / Place one quadrat by the hedge only / Place quadrats at regular intervals along a transect line) → Place quadrats at regular intervals along a transect linePrompt: A transect is a line across a habitat.
2. Five 1 m² quadrats contained these numbers of daisies: 2, 3, 12, 5, 2. What is the mean number of daisies per quadrat? → 4.8Prompt: Add up all the counts.

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