Length

Length means the measurement of how long something is or the distance between two places. Metres, centimetres, millimetres and kilometres are all units of length.

Units of length

In measurement, we use the word unit to describe what measurement we are using.
- Metre, centimetre, millimetre and kilometre are all units of length.
We write units after the number, using lower case letters.
- 5 m (five metres).
- 20 cm (twenty centimetres).
- 340 mm (three-hundred and forty millimetres).
- 10 km (ten kilometres).

Relations between units

If you look at your ruler, you will see it shows some units of length.
Most rulers show centimetres (cm) and millimetres (mm).
You can see that millimetres are smaller and centimetres are bigger.
- There are 10 millimetres in 1 centimetre.
- There are 100 centimetres in 1 metre.

Mixed units

Sometimes an object won't have an exact measurement in one unit.
- For example, a car is measured to be 4 and a half metres long.
That means the length of the car is the same as 4 metres plus 50 centimetres, which is half a metre.
We write this as 4 m 50 cm or 4 ¹/₂ m.

Measuring objects

You should use millimetres (mm) to measure small objects like the tip of a pencil.
You should use centimetres (cm) to measure medium-sized objects like books.
You should use metres to measure large objects like cars and classrooms.
You should use kilometres to measure very large distances, for example between towns and cities.

1Year 3 - Number

2Year 3 - Measurement

2.1Length

2.1.1Length

2.1.2Comparing Lengths

2.1.3Add & Subtract Lengths

2.1.4Perimeter

2.2Mass

2.2.1Mass

2.2.2Comparing Masses

2.2.3Add & Subtract Masses

2.3Volume & Capacity

2.3.1Volume & Capacity

2.3.2Comparing Volumes

2.3.3Add & Subtract Volumes

2.4Money

2.4.1Money

2.4.2Counting Money

2.4.3Adding & Subtracting Money

2.5Time

2.5.1Units of Time

2.5.2Clocks

2.5.3Telling the Time

2.5.4Time of the Day

2.5.512-Hour & 24-Hour Clocks

2.5.6Measuring Time

3Year 3 - Geometry

3.1Angles

3.1.1Angles in Degrees

3.1.2Types of Angle

3.2Properties of Shapes

3.2.12D Shapes

3.2.23D Shapes

3.3Straight Lines

3.3.1Straight Lines

3.3.2Parallel & Perpendicular Lines

4Year 3 - Statistics

4.1Statistics

4.1.1Statistics

4.1.2Pictograms & Bar Charts

5Year 4 - Number

6Year 4 - Measurement

6.1Units

6.1.1Metric Measurements

6.1.2Adding & Subtracting Money

6.2Time

6.2.1Converting Units of Time

6.2.2Changing the 12-Hour Clock to the 24-Hour Clock

6.2.3Changing the 24-hour Clock to the 12-Hour Clock

7Year 4 - Geometry

7.1Properties of Shapes

7.1.1Symmetry

7.1.2Types of Triangle

7.1.3Quadrilaterals

7.2Perimeter & Area

7.2.1Perimeter

7.2.2Area

7.3Position & Direction

7.3.1Coordinates

7.3.2Translation

8Year 4 - Statistics

8.1Statistics

8.1.1Types of Data

8.1.2Pictograms & Bar Charts

8.1.3Line Graphs

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