Repeatable Investigations: a skill companion
A small set of reusable sheets that grow one inquiry skill: planning an investigation that is fair, safe and repeatable, writing a method another group could follow, and checking the results with repeats and with a second group. Print the scaffolds once and slot them into the science lessons you are already teaching.
What a skill companion is
Inquiry skills are not a topic of their own. They grow inside the science units a class teaches all year, such as Habitat Conditions and Survival; Earth, Sun and the Day-Night Cycle; Electrical Circuits and Energy; and Reversible and Irreversible Changes. So this pack is not a full term of lessons. It is three reusable scaffolds, a map of where they fit, and a short stand-alone lesson for teaching the skill on its own first.
Start here: five minutes
- Read the pairing map on the next page: it shows which scaffold fits which science lesson.
- Print the planner and the results sheet, one each per group, whenever a lesson includes a test.
- Cut out the risk cards once. They are reused all year whenever a class plans for safety and permission.
- Open the free interactive unit on your board when you want a worked example of the skill.
- Run the one-page mini-lesson first if you want to teach the skill before folding it into a topic.
No science background needed
This pack is written for the busy generalist teacher. Each scaffold explains itself in plain words, and the answer sheet gives the card key, the worked results, a model plan for every Year 6 topic, and a quick three-level guide. The step up from Year 5 is the method: children choose a spread of values to test, write steps another group could follow, and call the investigation repeatable only when repeats, and a second group, give results close to their own.
Slot the skill into your science lessons
The same planning skill fits into every science unit. This map shows an investigation to plan in each Year 6 topic, its three kinds of variable with the values to try, the main risk or permission to plan for, and which scaffold to reach for. You do not run these as extra lessons; you fold them into the science you teach.
| When you teach | Investigation | Change, measure, control | Risk or permission | Scaffold |
|---|---|---|---|---|
| Habitat Conditions and Survival (AC9S6U01) | How does the amount of water each day affect how tall seedlings grow? | Change: 0, 10, 20, 30 and 40 mL a day. Measure: height in mm after 2 weeks. Control: seeds, soil, pot, light. Three pots each. | Wash hands after soil; ask before using the school garden beds. | Planner, then the results sheet |
| Earth, Sun and the Day-Night Cycle (AC9S6U02) | How does the time of day affect the length of a stick’s shadow? | Change: 9 am, 10 am, 11 am, noon. Measure: shadow length in cm. Control: the same stick, place and ruler. | Never look at the Sun; hats on; short turns outside. | Planner, then the risk cards |
| Electrical Circuits and Energy (AC9S6U03) | How does the length of a pencil-lead (graphite) path affect a bulb’s brightness? | Change: 2, 4, 6 and 8 cm between the clips. Measure: brightness on a light-meter app. Control: cells, bulb, wires, meter distance. | No short circuits; unclip a cell that feels warm. | All three, with the risk cards |
| Reversible and Irreversible Changes (AC9S6U04) | How does water temperature affect how long sugar takes to dissolve? | Change: 15, 30 and 45 °C. Measure: seconds to dissolve. Control: sugar, water, stirring. Three trials each. | An adult pours the hot water; a plastic or digital thermometer. | Results sheet, then a swap with another group |
| Any science topic | The class’s own investigable question | Children choose at least four evenly spread values, three repeats, and the things to control. | Children list the risks and who to ask. | Planner first, every time |
The three moves, and the picture that backs each one
When you want a worked example on the board, open the interactive unit and use the picture that matches the move children are working on.
- Name what to change, what to measure and what to control: “Plan the dissolving test: change the temperature, control the rest”.
- Choose equipment that lets you repeat trials safely: “Pick the setup that lets you repeat trials safely”.
- Keep only the steps that make the plan repeatable, safe and permitted: “Sort the planning actions for the dissolving investigation”.
How the scaffolds build the skill
The planner walks a group through every part of a plan, from the question and the values to try, to a numbered method and the permissions, and ends with a swap: can another group follow it? The results sheet records three trials of each value and the middle value, then sets one group’s results beside another’s. The risk cards match each hazard to the step that keeps it safe, including the permissions to seek before working in a garden or on Country or Place.
Plan it so others can repeat it
A repeatable investigation is one another group could follow from your plan alone and get the same kind of result. So the plan names every variable, the values you will try, how many repeats, and the steps in order.
Our question
Our variables
| We change (one thing only) | The values we will try (at least four, evenly spread) | ||
| We measure | Our tool and unit | ||
| We keep the same, and how | |||
We will test each value ______ times and use the middle value, because ________________________________
Our method
Write the steps in order, with amounts and units, so another group could do exactly what you did.
Risks, and permission
| What could go wrong, or who we must ask | What we will do |
|---|---|
Teacher note: if a group ticks “Not yet”, the questions the other group asked show the missing amounts, units or steps. Add them to the method, then swap again.
Repeat it, then compare with another group
Three trials of each value, and the middle value of the three, give a result you can trust. A trial far from the other two is a sign that something changed that should have stayed the same. When another group follows your method and gets close to your results, the investigation is repeatable.
A. Group 1’s sugar trials
Group 1 timed a level teaspoon of sugar dissolving in 200 mL of water, stirred the same way, three times at each temperature. An adult poured the warm and hot water. The times are in seconds.
| Water temperature | Trial 1 | Trial 2 | Trial 3 | Middle value |
|---|---|---|---|---|
| 15 °C | 95 | 98 | 96 | |
| 30 °C | 62 | 60 | 81 | |
| 45 °C | 41 | 43 | 42 |
B. Group 2 followed Group 1’s method
| Water temperature | 15 °C | 30 °C | 45 °C |
|---|---|---|---|
| Group 2’s middle values (seconds) | 97 | 61 | 44 |
C. Our results
| What we changed | Trial 1 | Trial 2 | Trial 3 | Middle value |
|---|---|---|---|---|
What could go wrong, and what do we do?
Cut out the cards. Match each numbered card (a risk, or a place where we must ask first) with the lettered plan step that deals with it. Then pick the cards that fit your own investigation and copy them into your plan.
Teacher note: each numbered card has exactly one plan step. The matches are on the answer sheet. Two numbered cards are about permission rather than danger: planning includes who to ask before investigating in a garden or on Country or Place.
Write a method another group can repeat
Use this stand-alone lesson to teach the skill on its own, before you fold it into a science topic. Paper helicopters give a quick, safe test whose drops really do vary, so the class sees why three trials matter, and a second group following the written method shows whether the investigation is repeatable.
We are learning to
- plan a fair test with values spread evenly and three repeats of each,
- write a method that another group could follow,
- judge whether our results are repeatable.
Success criteria
- I can write method steps in order, with amounts and units.
- I can say whether two groups’ results are close enough to call the test repeatable.
You need
- paper, scissors, paper clips, a ruler and a stopwatch or phone timer for each group, and a metre ruler,
- the planner and the results sheet (scaffolds 1 and 2), one each per group, and the risk cards from scaffold 3,
- the free interactive unit on your board, if you have one (optional).
Lesson flow (about 30 minutes)
| 5 min | One drop is not enough Drop one helicopter three times from the same height while three children time each drop. Ask: “Three timers, three times. Which one is right? What would make us surer?” |
| 10 min | Plan it Groups fill the planner: wing lengths 4, 6, 8 and 10 cm, one drop height, three drops each, and the risks. Show the board (see the box). Ask: “What would another group need to know to build and drop a helicopter exactly like ours?” |
| 10 min | Run and record Groups drop and time, standing on the floor, and record each trial and middle value in Part C of the results sheet. Ask: “One drop is far from the other two. What might have changed in that drop?” |
| 5 min | Swap the method Groups swap planners and check whether they could repeat each other’s test from the method alone. Ask: “What did the other group have to ask you? Add it to your method.” |
Running it shorter? Stop after the plan, and run and swap in your next science lesson.
Watch for these ideas
- Testing values bunched together, or only two values, so no pattern can show. Aim for four or more, evenly spread.
- A method with no amounts or units, such as “drop it from up high”. Ask: how high, exactly?
- Calling a test repeatable after one run of each, or quietly dropping a far-off trial instead of repeating it.
Make it easier, make it bigger
- Easier: give the wing lengths and the drop height; children write the steps and run the drops.
- Bigger: a second group follows the method, and the class graphs both groups’ middle values together.
Answers and look-fors
The next sheet has the risk-card key, the worked results with both groups, a model plan for each Year 6 topic, and a quick three-level guide.
Answers and look-fors
Risk cards
| Card | Risk, or where to ask first | Step | What keeps it safe, or permitted |
|---|---|---|---|
| 1 | A wire joined straight from one end of a cell to the other (a short circuit) | E | Always have a bulb or another part in the circuit, and unclip any cell that feels warm. |
| 2 | Hot water from the kettle | B | An adult boils and pours the water; the cups sit on a tray away from the table edge. |
| 3 | A glass thermometer that could break | G | Use a plastic-cased or digital thermometer, and lay it flat when not in use. |
| 4 | Nails left in salty water for a rusting test | A | Handle the nails with tongs or gloves, and wash hands afterwards. |
| 5 | Collecting creek water from bushland on Country | H | Ask the land custodians, including the Traditional Owners, before going; take only what you need. |
| 6 | Seedlings grown under a desk lamp | C | Keep the hot globe away from paper and leaves, and switch the lamp off at home time. |
| 7 | Measuring shadows in the playground at midday | F | Never look straight at the Sun; wear a hat and take short turns outside. |
| 8 | Using the school garden beds for a habitat test | D | Ask the person who looks after the garden first, and leave the beds as you found them. |
Results with repeats: the sugar trials
Middle values: 15 °C, 96 seconds; 30 °C, 62 seconds; 45 °C, 42 seconds. The odd trial is trial 3 at 30 °C (81 seconds), more than 5 seconds from the other two: the stirring stopped while the stopwatch ran, so that trial should be done again. The pattern: the warmer the water, the faster the sugar dissolved. Group 2’s middle values (97, 61, 44) are within 2 seconds of Group 1’s, so following the same method gave the same result: the investigation is repeatable.
Planner: what a good plan sounds like
| Topic | Variables, values and repeats | Risk or permission |
|---|---|---|
| Habitat Conditions and Survival | Change the water each day (0, 10, 20, 30 and 40 mL); measure the height in mm after 2 weeks; keep the seeds, soil, pot size and light the same; three pots for each amount. | Wash hands after handling soil; ask the person who looks after the garden before using its beds. |
| Earth, Sun and the Day-Night Cycle | Change the time (9 am, 10 am, 11 am and noon); measure the shadow of the same stick in cm, in the same place; repeat on three sunny days. | Never look straight at the Sun; wear hats and take short turns outside. |
| Electrical Circuits and Energy | Change the length of pencil lead between the clips (2, 4, 6 and 8 cm); measure the brightness on a light-meter app held 10 cm away; three readings each. | No short circuits: always a bulb in the circuit; unclip any cell that feels warm. |
| Reversible and Irreversible Changes | Change the water temperature (15, 30 and 45 °C); time a level teaspoon of sugar dissolving in 200 mL, stirred the same way; three trials each. | An adult boils and pours the water; use a plastic or digital thermometer. |
A quick three-level guide
| Move | Working towards | At standard | Beyond |
|---|---|---|---|
| Plan the variables | changes more than one thing at a time | names what to change, with a spread of values, what to measure and what to control | explains the choice of values and the number of repeats |
| Write a repeatable method | writes steps with no amounts or units | writes numbered steps with amounts and units that another group can follow | improves the method after a swap with another group |
| Judge repeatability | accepts a single run, or drops an odd trial without a repeat | uses middle values and compares them with another group | explains why two groups’ results can differ a little and still agree |
| Plan for risk and permission | names a risk without a safe step | matches each risk to a safe step and names who to ask | spots a risk or a permission in a new setting without help |
A child at standard plans a fair, safe test with a spread of values and repeats, writes a method another group can follow, and checks repeatability with middle values. The skill grows all year, so keep the scaffolds coming back.