• Quick retrieval from earlier learning (Homeostasis and negative feedback loops). Students answer on mini whiteboards.
• Show answers together and note who needs support in the main task.

1. In a control system, what role do these play: light-sensitive cells in the retina? (receptor / coordination centre / effector) → receptorPrompt: Detect → decide → respond.
2. What is negative feedback? (A change triggers a response that makes the change bigger / Bad news from a doctor / A response that never stops / A change triggers a response that reverses the change, back towards the set point) → A change triggers a response that reverses the change, back towards the set pointPrompt: Think of a thermostat in a house.
3. Homeostasis: which statement is NOT true? (Effectors can be muscles or glands. / In negative feedback, a rise in a value triggers changes that lower it. / Body temperature is kept close to 37 °C. / Receptors carry out the response.) → Receptors carry out the response.Prompt: Which part detects and which part responds?

• Ask everyone to find their pulse, then jump for 30 seconds and find it again.
• Share the objective: How the body warms up and cools down. Read the success criteria together.

• Work through the example out loud, saying why you do each step, not just what you do.
• Example: When does this happen: shivering?
• Step 1: When too cold, the body reduces heat loss and releases more heat.
• Step 2: So the answer is: response when too cold
• Answer: response when too cold
• 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. When does this happen: hairs lie flat? (response when too hot / response when too cold) → response when too hotPrompt: Does it help lose heat or keep it?
2. Which part of the brain monitors blood temperature? (the thermoregulatory centre (hypothalamus) / the retina / the spinal cord / the cerebellum) → the thermoregulatory centre (hypothalamus)Prompt: It sits at the base of the brain near the pituitary gland.

• 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.

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

1. When does this happen: sweating? (response when too hot / response when too cold) → response when too hotPrompt: Does it help lose heat or keep it?
2. A student writes "blood vessels move closer to the skin when you are hot". What is the correct idea? (Blood stops flowing to the skin / Vessels shrink and move deeper / Vessels near the skin widen, so more blood flows near the surface / The skin moves towards the vessels) → Vessels near the skin widen, so more blood flows near the surfacePrompt: Blood vessels do not move position.

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