3.2 Measure, measuring and measurement
Objectives
• Measure and draw lines to the nearest
millimetre
• Use names and abbreviations of units of
measurement to measure, estimate, calculate
and solve problems in everyday contexts
involving length, area
• Solve word problems and investigate in a
range of contexts: length, area and perimeter
• Make simple scale drawings
Starter (1) Oral and mental objective
Draw a ‘spider diagram’ on the board with numbers
on the legs. Write × or ÷ and one of 10/100/1000
on the body, and point to each leg in turn. Pupils
complete the calculations.
Starter (2) Introducing the lesson topic
Divide the board in two. Write a different
mathematical word related to measures at the top
of each half. Divide the class into two teams. Teams
then take turns to write a ‘measure’ word starting
with one letter of the previous word, e.g. ‘metre ~
estimate’. The team with more words wins.
Resources
Main lesson
− Ask pupils for the names of common units of measurement. (If you used
Starter 2, pupils can start by identifying any units from this list.) You may
need to explain the difference between metric and imperial units here. Ask
pupils to pick out length/mass/capacity units in order of size.
− Why do we use units?
How many millimetres are there in a centimetre? How many centimetres are
there in a metre? …
−
Use objects to show 1 litre, 5 ml, 1 kg, 1 g, 1 m, 15 cm, etc, for example
a litre drinks bottle, a medicine spoon (5 ml), 1 kg bag of sugar, a centicube
(1 g) …
• Mini whiteboards
• Main: Objects such
as a litre drinks bottle,
a medicine spoon,
a centicube, a 1 kg
bag of sugar etc, to
show some ‘standard’
measurements.
• Activity A: Scales for
weighing and rulers for
measuring.
E-book
1 Metric units
• Explanations
1 –
4
• Extra questions
• Worked solutions
• Quiz
• Competitive game
2 Converting metric units
Intervention
Ask pupils to use these ‘standards’ to estimate the measurements of other
objects.
Estimate the height of the classroom door. Estimate the capacity of this small
drinking glass?
− What do we mean by convert?
Demonstrate how to use the diagrams for a range of different examples.
How do you convert centilitres to litres? … kilometres to metres. What is 75
metres in centimetres? Stress that to convert to larger units you divide by a
multiple of 10, and that to convert to smaller units you multiply by a multiple
of 10.
1
• Access Book p34-42
− What is a scale? Where are they used?
Discuss what these scales mean: 1 cm to 1 m, 1 to
100, 1 : 100.
What does 1 : 1 represent? What does 1 : 2000
represent?
What scale would you use for a scale drawing of a
football pitch? … of a floor plan of a house? …of a
town map?
3 Scale
4 Using a scale
The scale of a model is 1:10. A length on the
model is 2.7cm. What is the corresponding actual
length?
Activity A
Encourage pupils to estimate before they weigh or
measure.
Activity B
Discuss solving this problem with the pupils.
Agree a definitive list of items that will be held in the
drawer. Pupils will need to measure these and ensure
that the sections of the desk are able to store all the
items agreed upon. Functional skills FS
Plenary
− Play ‘Quick Unit Bingo’. Ask pupils to draw a 3 × 3 grid and write in nine
different units of measure. These could include units of time and temperature.
Call out a range of questions such as ‘Which unit to measure the distance
from Paris to London?’ Pupils with km on their Bingo grid cross it off.
Continue until there is a winner.
Homework
Challenging Homework: A plank of wood weighs 1.4 kg. A length of 25 cm is cut
off the plank. The plank now weighs 0.8 kg. What was the original length of the plank?
Answers to textbook questions
( Highlighted answers have worked solutions on the e-book)
2 b)cm or mm c) g d) l
3 a)mm b) ml c) g
4 b)67.2 cm c) 4.5 kg d) 4600 g e) 250 cl f) 330 ml
5 No
6 1250 m
7 a)1.4 m b) 11 triangles c) 380 cm
8 a)Scale C 6.7 cm b) Scale A 5.4 cm c) Scale A 11.3 cm
d) Scale C 5.2 cm
9 a)i) 2.4 m ii) 0.6 m iii) 0.75 m b) line length 1.4 cm
2
Ref. 3.2 Maths at work
Ref. 4.1 Money skills
Websites
Discussion point
In pairs, pupils discuss
measuring they have done
outside school. When has it
been very important to get
it right? Share as a class.
Links
Scales are used with maps
in geography.
A clear distinction between
mass and weight is drawn
in science.
Misconceptions
When converting units,
pupils often divide instead
of multiplying and vice
versa. Emphasise that
when changing to smaller
units you multiply. It may
be helpful to compare with
money:
larger → smaller
£ → p (multiply
5 → 500 by 100)