• 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) 2 → 20 10 → 28 30 → 36 40 → 44 10 → 52 What happens to “Bulb brightness (lux)” as “Number of cells” increases? (it increases / it decreases / it goes up then down / it stays the same) → it increasesPrompt: Read down the second column. Are the numbers getting bigger or smaller?
2. Water temperature (°C) → Time to dissolve (s) 5 → 51 20 → 45 15 → 39 40 → 33 10 → 27 What happens to “Time to dissolve (s)” as “Water temperature (°C)” increases? (it decreases / it stays the same / it increases / it goes up then down) → it decreasesPrompt: Read down the second column. Are the numbers getting bigger or smaller?
3. Water temperature (°C) → Time to dissolve (s) 5 → 50 20 → 44 6 → 38 8 → 32 50 → 26 What happens to “Time to dissolve (s)” as “Water temperature (°C)” increases? (it decreases / it stays the same / it increases / it goes up then down) → 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 temperature rise in a reaction three times: 10, 8 and 10 °C. What is the mean? Give your answer to 1 decimal place. → 9.3 °CPrompt: Add the three readings.
2. Four repeat readings of the time for a ball to roll down a ramp (s): 31, 33, 43, 33. Which reading is anomalous (does not fit the pattern)? (43 / 31 / 33) → 43Prompt: 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 a pulse rate after exercise (bpm): 185, 135, 139, 136. Leave out the anomalous reading and work out the mean of the rest, to 1 decimal place. → 136.7 bpmPrompt: First find the reading that does not fit.
2. A group measured the time for a ball to roll down a ramp three times: 31, 29 and 34 s. What is the mean? Give your answer to 1 decimal place. → 31.3 sPrompt: Add the three readings.

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