Page 7 - STEPS MATHEMATICS 3B: A SCHEME OF WORK FOR LEVEL 3 NATIONAL CURRICULUM MATHEMATICS - TEACHER'S HANDBOOK

15. AREA & PERIMETER

LEARNING CONTEXT Mathematics in the
National Curriculum
Contribution made by this Step
Programmes of Study
The children estimate and find the areas and perimeters of No statutory reference to area
various shapes. Some work is included on calculating simple and perimeter.
perimeters in centimetres and areas in square centimetres. Pupils should be taught to:
KS1
• make common 3-D and 2-D
Objectives shapes and models, working with
increasing care and accuracy;
To enable children to: begin to classify shapes according
a Estimate and find areas by counting unit tiles and perimeters to mathematical criteria. (SSM 2.b)
by counting unit lengths. • begin to use a wider range of
b Start to use the square centimetre as a standard unit. standard units, including standard
• c Start to measure and construct closed shapes with sides an units of time, choosing units
exact number of centimetres long. appropriate to a situation; esti-
mate with these units. (SSM 4.a)
• understand general statements,
Background and investigate whether particular
cases match them. (UA 4.c)
In Step 3a:25, the children estimated and measured the areas of KS2
regular and non-regular surfaces in various square units, • make 2-D and 3-D shapes and
including the square decimetre and the square metre. patterns with increasing accuracy,
In Step 3a:35, the focus was on perimeters and finding recognise their geometrical
perimeters by counting unit lengths, and recognising that not all features and properties, and use
these to classify shapes and solve
shapes with the same area had the same perimeter, and not all problems. (SSM 2.b)
those with the same perimeter had the same area. This work is • choose appropriate standard
extended as the children now start to measure areas in square units of length, mass, capacity
centimetres and perimeter in whole centimetres. and time, and make sensible
It is important to keep stressing that area is a measure of the estimates with them in everyday
amount of surface of a given shape or solid whose surfaces may situations. (SSM 4.a)
be plane or curved and of any texture or material. Similarly, • find perimeters of simple
shapes; find areas and volumes by
• counting methods, leading to the
perimeter is a measure of the distance around a closed shape.
use of other practical methods,
e.g. dissection. (SSM 4.c}
THINKING AND TALKING • understand and investigate
general statements. (UA 4.a)
MATHEMATICALLY

Starting points for discussion

Revising meaning of 'open' and 'closed' shapes, 'area', 'perimeter'.
How can you measure the amount of surface inside a closed
shape? Key language
estimate, measure,
Miniature collection: objects with a surface/face/total area of
about one square centimetre. enclose, cover, area,
surface, amount, unit
Draw another shape which has an area about the same size as ... square, unit length,
this book cover, your hand, etc. approximately, right-
centimetre square, about,
Revise the terms, 'square decimetre' and 'square metre', What
• angled corners, diagonal,
can you tell me about these? How can you make these? How can
closed
you use them?
STEPS 3b 149