Measuring with Precision: a skill companion
A small set of reusable sheets that grow one inquiry skill: choosing a tool precise enough for the change you want to see, reading digital displays to a sensible number of digits, repeating readings, and recording every value with its unit. 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 precise-enough sheet and the displays sheet, one each per child, whenever a lesson measures something.
- Cut out the record cards once. They are reused all year whenever a class checks its records.
- 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 every choice and record, the card key, a model record for every Year 6 topic, and a quick three-level guide. The step up from Year 5 is judgement: a tool must be precise enough for the change you want to see (a kitchen scale cannot show a few hundredths of a gram), and a display can show more digits than you can trust (a stopwatch started by hand is only good to about two tenths of a second).
Slot the skill into your science lessons
The same measuring skill fits into every science unit. This map shows something to measure in each Year 6 topic, the tool and the precision to read it to, a digital option, 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 | Measure | Tool and precision | Digital option | Scaffold |
|---|---|---|---|---|
| Habitat Conditions and Survival (AC9S6U01) | Seedling height each day; the temperature in a sunny and a shady spot | A millimetre ruler; a digital thermometer to 0.1 °C | A light-meter app for the light each spot gets | Precise enough?, then the record cards |
| Earth, Sun and the Day-Night Cycle (AC9S6U02) | A stick’s shadow each hour; sunrise and sunset times | A tape measure to the centimetre; times to the minute | A weather website or app for sunrise and sunset | Precise enough?, then the displays sheet |
| Electrical Circuits and Energy (AC9S6U03) | Voltage and current in a circuit; a bulb’s brightness | A multimeter to 0.01 V or 0.01 A, on the right range | A light-meter app or a light sensor that logs | The mini-lesson, then the displays sheet |
| Reversible and Irreversible Changes (AC9S6U04) | The mass a rusting nail gains; how long sugar takes to dissolve | A balance to 0.001 g; a stopwatch, recorded to 0.1 s when timed by hand | A data logger with a temperature probe | All three, with the record cards |
| Any science topic | Whatever the class’s investigation measures | Children choose a tool whose smallest step is small enough to see the change | Children decide whether a digital tool helps | Precise enough? first |
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.
- Copy a digital display with its unit, and see the readings as a table and a graph: “Read the multimeter: log voltage as the supply is raised” and “Record brightness: a light sensor logs each bulb reading”.
- Check a record for a reading that does not fit, and measure it again: “Spot the current reading to measure again”.
- Tell a precise reading from a rushed one: “Decide which readings were measured with reasonable precision”.
How the scaffolds build the skill
The precise-enough sheet sets five changes to detect against two tools each, and asks which tool’s smallest step is small enough, and which reaches far enough. The displays sheet records six digital displays to a sensible number of digits, then repeats readings and finds the one to measure again. The record cards sort precise records from rushed ones, each for a reason children can name.
Is the tool precise enough?
A tool is precise enough when its smallest step is much smaller than the change you want to see: about a fifth of it, or smaller. It must also reach far enough to measure the biggest value. Tick the tool you would use, and say why.
A. Choose the tool
| The change to see | Tool 1 | Tool 2 | Why? |
|---|---|---|---|
| The mass a nail gains as it rusts for five days (about 0.03 g) | □ an electronic balance reading to 0.001 g, up to 100 g | □ a kitchen scale reading to 1 g, up to 5 kg | |
| How much warm water cools in one minute (about 0.8 °C) | □ a digital thermometer reading to 0.1 °C | □ a thermometer with a mark every 1 °C | |
| How much a bean seedling grows in a day (about 6 mm) | □ a ruler marked in centimetres only | □ a ruler marked in millimetres | |
| How much a stick’s shadow shortens from 9 am to 10 am (about 30 cm, on a shadow up to 1.5 m long) | □ a 30 cm ruler marked in millimetres | □ a 5 m tape measure marked in centimetres | |
| How much a cell’s voltage drops as it runs down (about 0.05 V) | □ a multimeter on its 20 V range, reading to 0.01 V | □ a multimeter on its 200 V range, reading to 0.1 V |
B. Our investigation
Teacher note: a child who always picks the finest tool has missed the second test. In the shadow row, a 30 cm ruler marked in millimetres is finer but too short, so a 5 m tape measure marked in centimetres is the right choice.
Record what the display shows, sensibly
A digital tool shows digits, and usually you copy them all, with the unit. But a display can show more digits than you can trust: a stopwatch started and stopped by hand is only good to about two tenths of a second, whatever it shows.
A. Record each display
Write each reading as you would record it, with its unit. Circle any display where you would not copy every digit.
B. Repeat it
1. The current through a bulb was read three times: 0.21 A, 0.20 A, 0.21 A. What would you record? ____________
2. Three groups read the same cell’s voltage: 1.52 V, 1.51 V, 1.15 V. Which reading should be measured again, and what might have gone wrong? ________________________
C. Our readings
| What we measured | Tool and smallest step | Reading 1 | Reading 2 | Reading 3 | We record |
|---|---|---|---|---|---|
Precise, or not precise?
Cut out the cards. Lay down the two grey heading cards, then sort the records under them. For each record that is not precise, say what is wrong and write it again on a blank card.
Teacher note: 6 records are precise and 6 are not. The answer sheet lists which is which, and why. Card H has the most digits of all and is still not precise, because a hand-timed stopwatch cannot give them.
How many digits can you trust?
Use this stand-alone lesson to teach the skill on its own, before you fold it into a science topic. A ball dropped from 1 m and timed by hand shows that a stopwatch’s hundredths cannot be trusted, and the thickness of one sheet of paper shows how to measure something thinner than a ruler’s finest mark. The scaffolds then put both ideas to work.
We are learning to
- choose a tool that is precise enough for the change we want to see,
- record a display to a sensible number of digits, with its unit,
- repeat readings, and measure again any that do not fit.
Success criteria
- I can explain why a hand-timed 0.43 seconds is better recorded as about 0.4 seconds.
- I can measure the thickness of one sheet of paper with a millimetre ruler.
You need
- a tennis ball, a metre ruler, a stopwatch or phone timer for each pair, a stack of 100 sheets of paper and a millimetre ruler,
- the precise-enough sheet and the displays sheet (scaffolds 1 and 2), one each per child, and the record cards from scaffold 3,
- the free interactive unit on your board, if you have one (optional).
Lesson flow (about 30 minutes)
| 5 min | Time a drop Drop the ball from 1 m while five pairs time it. Write all five times on the board. Ask: “Five stopwatches, five different hundredths. Which digits can we trust?” |
| 10 min | Too thin to measure? Pairs try to measure one sheet of paper with a ruler, then measure the stack of 100 and divide by 100. Ask: “The ruler’s finest mark is a millimetre. How did we measure a tenth of one?” |
| 10 min | Precise enough? Children do scaffold 1 and Part A of scaffold 2. Show the board (see the box). Ask: “Why can the kitchen scale not show the rust on a nail?” |
| 5 min | Sort the records Tables sort the record cards under the two heading cards. Ask: “This record has the most digits of all. Why is it still not precise?” |
Running it shorter? Stop after the two challenges, and do the scaffolds in your next science lesson.
Watch for these ideas
- Copying every digit a display shows, even when the measurement cannot be that precise, as with hand timing.
- Choosing the finest tool even when it is too short or too small for the job.
- Rubbing out a reading that does not fit, instead of measuring it again.
Make it easier, make it bigger
- Easier: in scaffold 1, ask of each tool only “Is its smallest step small enough?” before thinking about reach.
- Bigger: film the ball drop in slow motion on a tablet, time it from the video, and compare with the hand times.
Answers and look-fors
The next sheet has every tool choice and display record, the repeated readings, the card key, a model record for each Year 6 topic, and a quick three-level guide. A ball dropped from 1 m takes about 0.45 seconds to land.
Answers and look-fors
Is the tool precise enough?
| Row | Use | Why the other tool will not do |
|---|---|---|
| 1 | Tool 1: an electronic balance reading to 0.001 g, up to 100 g | its step of 1 g is too big to show the change |
| 2 | Tool 1: a digital thermometer reading to 0.1 °C | its step of 1 °C is too big to show the change |
| 3 | Tool 2: a ruler marked in millimetres | its step of 10 mm is too big to show the change |
| 4 | Tool 2: a 5 m tape measure marked in centimetres | it reaches only 300 mm, and the biggest value is 1500 mm |
| 5 | Tool 1: a multimeter on its 20 V range, reading to 0.01 V | its step of 0.1 V is too big to show the change |
Displays and repeats
Multimeter (volts): 2.94 V (copy every digit the meter gives, with the unit). Stopwatch, timed by hand: 12.4 s (hand timing is only good to about two tenths of a second). Digital thermometer: 23.6 °C (copy the tenths the thermometer gives). Light-meter app: 318 lux (copy the whole number, with the unit). Electronic balance: 8.462 g (a fine balance gives thousandths: keep them). Kitchen scale: 152 g (it reads whole grams only). The current: 0.21 A, the middle of the three readings. The cell: 1.15 V should be measured again; the other two agree, and it looks like two digits swapped.
Record cards
| Card | Pile | Why |
|---|---|---|
| A | Precise | the finest mark, with its unit |
| B | Not precise | a guess, with no unit |
| C | Not precise | rounded off too soon |
| D | Not precise | a word, not a measurement |
| E | Precise | copied from the display, with its unit |
| F | Precise | as fine as hand timing allows |
| G | Precise | every digit the balance gives |
| H | Not precise | more digits than a hand-timed stopwatch can give |
| I | Precise | the tenths the thermometer gives, with the unit |
| J | Not precise | the scale reads whole grams; the gain was a few hundredths of a gram |
| K | Precise | copied from the display, with its unit |
| L | Not precise | rounded to the metre; the tape reads centimetres, such as 127 cm |
What a precise record sounds like
| Topic | A record at standard |
|---|---|
| Habitat Conditions and Survival | Seedling B on day 5: 47 mm (millimetre ruler). Shady spot at noon: 18.4 °C (digital thermometer). |
| Earth, Sun and the Day-Night Cycle | Shadow at 10 am: 127 cm (tape measure). Sunset: 5:42 pm (weather website). |
| Electrical Circuits and Energy | Voltage across the bulb: 2.94 V; current through it: 0.21 A (multimeter, each read three times). |
| Reversible and Irreversible Changes | Nail mass: 8.462 g before, 8.493 g after five days in salt water (electronic balance). Dissolving time: 42 s (by hand). |
A quick three-level guide
| Move | Working towards | At standard | Beyond |
|---|---|---|---|
| Choose a precise enough tool | picks any tool that measures the right thing | picks a tool whose smallest step is small enough for the change, and that reaches far enough | measures many to measure one, such as 100 sheets of paper |
| Record with sensible precision | rounds off too soon, or leaves out the unit | copies the display with its unit, and rounds hand timing sensibly | explains how many digits a measurement can be trusted to |
| Repeat and check | takes one reading only | repeats readings, records the middle value, and measures again one that does not fit | suggests what went wrong with an odd reading |
A child at standard chooses a tool precise enough for the change, records each reading with its unit to a sensible number of digits, and repeats readings. The skill grows all year, so keep the scaffolds coming back in every science topic.