2D Shapes - Planet Maths Download

2D Shapes
Strand: Shape and Space
Strand unit: 2D Shapes
Curriculum Objectives
Make informal deductions about 2D shapes and their properties.
Use angle and line properties to classify and describe triangles and quadrilaterals.
Construct triangles from given sides or angles.
Tessellate combinations of 2D shapes.
Classify 2D shapes according to their lines of symmetry.
Use 2D shapes and properties to solve problems.
Looking back: What the 5th class programme covered
1. Using angle and line properties to classify and describe triangles.
2. Using angle and line properties to classify and describe quadrilaterals.
Maths skills used in this topic
1. Applying and problem-solving: Plan and implement solutions to problems in a variety of
2. Communicating and expressing: Communicate and express mathematical ideas, processes
and results in oral and written form.
3. Integrating and connecting: Make mathematical connections within mathematics itself,
throughout other subjects, and in applications of mathematics in practical everyday contexts.
4. Reasoning: Reason systematically in a mathematical context.
5. Implementing: Implement suitable standard and non-standard procedures with a variety of
tools and manipulatives.
Concrete materials
Protractor, ruler, compass, pencil, coloured paper, squared paper, 2D shapes
Equilateral triangle, isosceles triangle, scalene triangle, right-angled triangle, rhombus, square,
rectangle, parallelogram, trapezium, kite, polygon, closed shapes, regular polygon,
irregular polygon, quadrilateral, extend, angle, symmetrical, line(s) of symmetry,
decagon, heptagon, octagon, oval, trapezium, tessellating, protractor, nonagon
Teaching points
Revise the properties of the 2D shapes already studied up to 5th class in terms or number of sides,
number of corners/vertices and length of sides. Children should be encouraged to discuss the
similarities and differences between the shapes. It is very important that there are visual aids in
the classroom so that the children have a reminder of the appearance of each shape. The children
need to manipulate the shapes, draw them and construct them using Geoboards, plasticine,
geostrips and templates. Straws can also be used to construct each shape or
lollipop sticks with Blu-tac holding the corners together. The children also need to
explore the tessellating properties of various shapes.
Oral and mental activities
Show number of sides on a hexagon, a triangle, pentagon, octagon, etc. Revise tables. Show
number of lines of symmetry in any shape.
Loop game (see Folens Online resources)
2D shapes:
Children call out the attributes of a shape and the other children guess the shape.
Topic suggestions
1. Design an alien using a combination of regular 2D shapes.
2. On the internet examine bridges and buildings to discover which 2D shapes are evident in
their construction and outward appearance.
3. Look at patterns for Aran knitted jumpers and scarves. Investigate the various 2D shapes in
the knitting pattern.
4. Design a bathroom/kitchen floor tiling scheme.
5. Discuss the origins of the names of the 2D shapes and the meanings of these words which
give a clue to their shape, e.g. ‘quad’, ‘octo’, ‘deca’, ‘nona’, ‘penta’.
6. Classify the shapes using different criteria, e.g. size of angles, parallel sides, lines of symmetry,
equal sides, perpendicular sides.
7. Use tangrams to make various polygons.
8. Work in pairs to give instructions on constructing various triangles. One child gives the
instructions while the other draws the triangle. Then the children swap roles.
Activity A
Pick out the correct shape from the photograph
1. Put the number 1 over the hemisphere, the number 2 over the pentagon, the number 3
over the kite, the number 4 over the trapezium, the number 5 over the hexagon and the
number 6 over the octagon.
2. What is the name of the headquarters of the United States Department of Defense? Why
has it been given this name? (pentagon, because of its shape)
3. A kite has ________ pairs of sides of equal length. (2)
4. How many sides has a decagon? (10)
5. How many sides has a nonagon? (9)
Lower attainers:
Separate activity sheet
Higher attainers:
Separate activity sheet
1. Triangles have __________ sides.
1. Name these shapes.
Equilateral triangle
Isosceles triangle
Scalene triangle
(i) ____ sides equal
(i)____ sides equal
(i)____ sides equal
(ii) ____ angles equal
(ii)____ angles equal
(ii)____ angles equal
2. Show the lines of symmetry in each of the shapes below.
2. Quadrilaterals have _______ sides.
3. Name the different shapes that you see.
____ sides equal length
____ sides equal length
____ sides equal length
Opposite sides are p________
Opposite sides are p________
Opposite sides are p________
____ right angles
____ acute angles
____ right angles
____ obtuse angles
(b) A parallelogram with two sides 6cm and two sides 4cm
1 set of ____
Adjacent sides ____________
4. Draw the following 5 shapes.
(a) A square with sides 4cm
(c) An equilateral triangle with each side 4cm long
____ sides equal
(d) An isosceles triangle with two sides 4cm long and the third side 5cm long
Opposite sides are p________
(e) A scalene triangle with three sides 3cm, 4cm and 5cm long
____ acute angles
Which of the 5 shapes tessellate?
____ obtuse angles
(a) 2cm ____
(b) 2cm ____
(c) 3cm ____
(e) 4cm ____
(f) 5cm ____
(g) 4cm ____
Name: _______________________________________
(d) 4cm ____
Date: ___________________
Page 137: 2D Shapes
3. Using your protractor construct triangle with
(a) Two sides measuring 5cm and 6.5cm and an angle of 75°
(b) Two sides measuring 4cm and 6cm and an angle of 40°
(c) Two sides measuring 4.5cm and 4.5cm and an angle of 90°
(d) Two sides measuring 5cm and 4cm and an angle of 120°
Name: _______________________________________
Date: ___________________
© Folens Photocopiables
© Folens Photocopiables
5. Using all or some of these 7 lengths, draw the different types of shapes you can make.
Page 138: 2D Shapes
Shape and Space: 3D shapes, lines and angles, spatial awareness
Measures: Length, area
Number: Fractions, symmetry, pattern
Art: Pattern making – tessellating patterns for tiling, drawing regular patterns, drawing irregular
patterns using various 2D shapes, fold-over painting for symmetry
SESE Geography: 2D shapes in the environment
SESE History: Studying coats of arms and investigating 2D shapes, development of the wheel
SESE Science: 2D shapes found in the natural world
Maths at home/parental involvement
1. Examine various tessellated tile patterns in shopping centres, shops, bathrooms, kitchens,
floors, walls, hotels, etc.
2. Look out for 2D shapes at home in wallpaper, magazines, newspapers, packaging, food
wrappers, etc.
3. Spotting different angles and triangles in our everyday environment and identify
symmetrical shapes and pictures in everyday life.