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Practice in drawing
to nearest mm. Eg: Ask pupils to draw & then
measure a line 9 squares long on non-standard squared
paper.
Nearest is winner. Repeat for other lengths.
(Know 1 square length in advance so you can just
calculate each suggested length without measuring) |
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- use ruler to
measure & draw lines to nearest mm
and
- use protractor to measure & draw angles to
nearest degree, (including reflex angles) |
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construct
draw, sketch
measure
perpendicular
distance
ruler
protractor (angle measure)
set square
angle
degree (°)
right angle
acute angle
reflex angle
length
millimetre (mm)
centimetre(mm) |
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Length
Measurement:
Ask pupils to place these lines in order of decreasing
length. (Why do we need to measure for small differences?).
Eg;
OHS
SSM3/6: Measuring Lengths
OR
Angle Measurement:
Ask volunteers to measure angles on OHS such as:
OHS
SSM3/4: Angle Rules OK
Note;
Use to reinforce accurate use of ruler & protractor.
Make clear that accuracy is + / - 1mm and + / -
1° |
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Activities involving
- Measuring & drawing lines to nearest mm
- Measuring & drawing angles to nearest degree
- Extend to problems requiring accuracy targets
to be met.
Eg: Demonstrate how to construct hexagon using protractor
(- or shortcut with pair of compasses, for complementary
skills) & use in WS
SSM3/1: An Optical Illusion?
( Each pupil constructs a hexagon & shades it
so appears as a 3-d cube. Tessellating hexagons
appear to be form an optical illusion.
Reinforce accuracy requirements: explain that when
cut out and stuck together, the group's hexagons
should make an impressive optical illusion - but
only if to nearest mm and degree. Gaps due to badly
fitting hexagons destroys the illusion. |
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Recap accurate
use of rulers and protractors; most common errors
WS
SSM3/1: An Optical Illusion?
- Stick all finished hexagons together on A1 sheet.
Do they meet the accuracy requirements? |
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Sparks
20: Angles 1:
Estimate angles - closest is winner; (can use a
paper corner to estimate 90° & 45°). |
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and
- construct given 2 sides & enclosed angle (SAS)
and
- construct , given 2 angles and included side
- (ASA) |
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Demonstrate (ASA)
construction of:
Triangle ABC with:
Angle A = 36°
Angle B = 58°
Side AB = 7cm
Demonstrate (SAS) construction of:
Triangle ABC with:
Side AB = 6cm
Side AC = 10cm
Angle A = 42° |
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Further constructions,
given SAS or ASA
Extend to more complex constructions, given time
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