• 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. Number of cells → Bulb brightness (lux) 10 → 22 20 → 28 30 → 34 40 → 40 10 → 46 What happens to “Bulb brightness (lux)” as “Number of cells” increases? (it decreases / it stays the same / it increases / it goes up then down) → it increasesPrompt: Read down the second column. Are the numbers getting bigger or smaller?
2. Distance from lamp (cm) → Bubbles from pondweed per minute 5 → 56 4 → 48 30 → 40 8 → 32 10 → 24 What happens to “Bubbles from pondweed per minute” as “Distance from lamp (cm)” increases? (it goes up then down / it increases / it stays the same / it decreases) → it decreasesPrompt: Read down the second column. Are the numbers getting bigger or smaller?
3. Number of cells → Bulb brightness (lux) 5 → 33 20 → 36 30 → 39 8 → 42 25 → 45 What happens to “Bulb brightness (lux)” as “Number of cells” increases? (it decreases / it stays the same / it goes up then down / it increases) → it increasesPrompt: 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 how far a toy car travelled three times: 63, 61 and 60 cm. What is the mean? Give your answer to 1 decimal place. → 61.3 cmPrompt: Add the three readings.
2. Four repeat readings of the time for a ball to roll down a ramp (s): 40, 42, 55, 40. Which reading is anomalous (does not fit the pattern)? (55 / 42 / 40) → 55Prompt: 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 time for a ball to roll down a ramp (s): 38, 40, 36, 51. Leave out the anomalous reading and work out the mean of the rest, to 1 decimal place. → 38 sPrompt: First find the reading that does not fit.
2. Four repeat readings of the time for a ball to roll down a ramp (s): 24, 23, 32, 25. Which reading is anomalous (does not fit the pattern)? (32 / 25 / 24 / 23) → 32Prompt: Most of the readings are close together.

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