Lesson Plan – Lesson 6 Surface Area

Lesson Plan – Lesson 6 Surface Area
Objectives and Habits of Mind
•To identify edges, faces and vertices (Level 3/ 4)
•To find the surface area of a cube (Level 5)
•To find the surface area of a cuboid (Level 6)
•To find the surface area of 3D shapes from nets. (Level 7)
•To work well in a group, listening attentively and taking on different roles when needed.
•To negotiate and follow ground rules, to ensure fairness and cooperation when working with
others.
Keywords
Face, Surface Area, Vertex, Edge,
Mental and Oral Starter
Pupils to say how many faces, vertices and edges each 3D shape has.
Main Activity
Each member of the group should select a 3D shape to work on and cut it out. Pupils to write down the number
of faces, edges and vertices the shape has. Pupils then calculate the surface area of their chosen shape.
They then glue the shape onto the group’s A3 paper and write down how they worked it out, checking that the
rest of the group agree with their method. Pupils can use the nets provided to work out the surface area of some
of the shapes.
Support - provide 3D models for the pupils.
Plenary
Pupils to reflect on the success criteria.
LO To find the surface area of 3D
shapes
RAG
Key Words: Face, Edge, Vertex, Surface Area
11-Jan-17
Starter Activity
How many vertices, edges and faces?
Can you
name any
of these
solids?
Level
Shape
Space
Measure
3/4
I can identify
edges, faces and
vertices
5
I can find the
surface area of a
cube
6
7 /8
I can find the surface area
of a cuboid.
I can calculate
volumes and surface
area of cylinders.
I am starting the lesson on level _____________________
By the end of this lesson I want to be able to _____________________
Starter Activity
How many vertices, edges and faces?
Starter Activity
How many vertices, edges and faces?
Surface area of a cube
How can we find the surface area of a cube of length 4cm?
All six faces of a cube have the same
area.
The area of each face is 4 × 4 = 16
Therefore,
4
Surface area of a cube = 16 x 6 = 96cm2
Surface area of a cuboid
To find the surface area of a cuboid, we calculate the total
area of all of the faces.
A cuboid has 6 faces.
The top and the bottom of the
cuboid have the same area.
The sides of the cuboid have the
same area.
The front and the back of the
cuboid have the same area.
8
6
4
Surface area of a cuboid =
2 × (8 × 4)
Top and bottom
+ 2 × (6 × 8)
Front and back
+ 2 × (6 × 4)
Left and right side
Surface area of a cuboid = (2×32) + (2×48) + (2×24)
Working out surface are from nets.
Here is the net of a triangular based pyramid (tetrahedron.)
What is its surface area?
Area of each face = ½bh
= ½ × 6 × 5.2
= 15.6 cm2
5.2 cm
Surface area = 4 × 15.6
= 62.4 cm2
6 cm
Here is the net of a triangular prism.
What is its surface area?
13 cm
10 cm
60
12 cm
We can work out the area of
each face and write it in the
diagram of the net.
260
200
260
60
Then add each area
together to get the total
surface area
= 60 + 60 + 200 + 260 + 260
= 840 cm2
20 cm
Here is the net of a Surface area of a
cylinder
3
5
?
Circumference
To find the surface area
find the area of the
rectangle and the area
of the circles and add
them together.
The rectangles wraps
around the circles so
the length of the
rectangle is the same
as the circumference of
the circles.
Today’s Task
In your groups
Each member of the group should select a 3D shape to
work on and cut it out.
Write down the number of faces, edges and vertices the
shape has.
Find the surface area of the shape.
Glue the shape onto the group’s A3 paper and write down
how you worked it out. The rest of your group must agree
with your method.
Cubes
Cuboid
5m
4cm
3
2m
7m
Triangular Prism
Cuboids
Cylinder
2m
3cm
5cm
4cm
4cm
6cm
6cm
Square Based Pyramid
12m
5m
30m
3m
10cm
4.5m
30m
6m
2m
3m
12m
4m
10cm
5cm
30cm
6cm
30cm
4cm
Find the surface area of a ...........
Work out the area of each face.
Your working out will go in here.
Your answer in cm2