• Quick retrieval from earlier learning (Reading tables and line graphs). Students answer on mini whiteboards.
• Show answers together and note who needs support in the main task.

1. Distance from lamp (cm) → Bubbles from pondweed per minute 10 → 59 10 → 53 15 → 47 20 → 41 25 → 35 What happens to “Bubbles from pondweed per minute” as “Distance from lamp (cm)” increases? (it goes up then down / it decreases / it stays the same / it increases) → it decreasesPrompt: Read down the second column. Are the numbers getting bigger or smaller?
2. Distance from lamp (cm) → Bubbles from pondweed per minute 2 → 41 10 → 36 30 → 31 8 → 26 50 → 21 What happens to “Bubbles from pondweed per minute” as “Distance from lamp (cm)” increases? (it goes up then down / it stays the same / it decreases / it increases) → it decreasesPrompt: Read down the second column. Are the numbers getting bigger or smaller?
3. Water temperature (°C) → Time to dissolve (s) 2 → 55 4 → 50 30 → 45 20 → 40 50 → 35 What happens to “Time to dissolve (s)” as “Water temperature (°C)” increases? (it goes up then down / it increases / it decreases / it stays the same) → it decreasesPrompt: Read down the second column. Are the numbers getting bigger or smaller?

• Show a simple experiment with one thing changed and ask what makes it a fair test.
• Share the objective: Repeat readings, means and anomalies. Read the success criteria together.

• Work through the example out loud, saying why you do each step, not just what you do.
• Example: A group measured a pulse rate after exercise three times: 103, 101 and 100 bpm. What is the mean? Give your answer to 1 decimal place.
• Step 1: 103 + 101 + 100 = 304
• Step 2: 304 ÷ 3 = 101.33
• Step 3: So the answer is: 101.3 bpm
• Answer: 101.3 bpm
• 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 group measured the time for a ball to roll down a ramp three times: 27, 28 and 26 s. What is the mean? Give your answer to 1 decimal place. → 27 sPrompt: Add the three readings.
2. Four repeat readings of a pulse rate after exercise (bpm): 165, 120, 121, 119. Which reading is anomalous (does not fit the pattern)? (165 / 120 / 121 / 119) → 165Prompt: Most of the readings are close together.

• 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. Four repeat readings of the temperature rise in a reaction (°C): 17, 17, 6, 15. Leave out the anomalous reading and work out the mean of the rest, to 1 decimal place. → 16.3 °CPrompt: First find the reading that does not fit.
2. Four repeat readings of the time for a ball to roll down a ramp (s): 22, 21, 20, 12. Which reading is anomalous (does not fit the pattern)? (12 / 20 / 22 / 21) → 12Prompt: Most of the readings are close together.

Free online practice with hints and printable worksheets for this skill: eurekami.com/science/grade-6.