Cubes and cuboids

Lesson Plan – Lesson 6 Surface Area

Mental and Oral StarterPupils to say how many faces, vertices and edges each 3D shape has.

Main ActivityEach 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.

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,

LO To find the surface area of 3D shapes

RAG

Key Words: Face, Edge, Vertex, Surface Area

Can you name any of these solids?

Starter ActivityHow many vertices, edges and faces?

3 May 2023

Level 3/4 5 6 7 /8ShapeSpaceMeasure

I can identify edges, faces and vertices

I can find the surface area of a cube

I can find the surface area of a cuboid.

I can calculate volumes and surface area of cylinders.

Today we are learning

I am starting the lesson on level _____________________

By the end of this lesson I want to be able to _____________________

Starter ActivityHow many vertices, edges and faces?

Starter ActivityHow many vertices, edges and faces?

How can we find the surface area of a cube of length 4cm?

Surface area of a cube

4

All six faces of a cube have the same area.

The area of each face is 4 × 4 = 16

Therefore,

Surface area of a cube = 16 x 6 = 96cm2

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.

Surface area of a cuboid

The sides of the cuboid have the same area.

The front and the back of the cuboid have the same area.

Surface area of a cuboid =

6

8 4

2 × (8 × 4) Top and bottom

+ 2 × (6 × 8) Front and back

Surface area of a cuboid = (2×32) + (2×48) + (2×24)

Here is the net of a triangular based pyramid (tetrahedron.)

Working out surface are from nets.

What is its surface area?

6 cm

5.2 cm

Area of each face = ½bh

= ½ × 6 × 5.2

= 15.6 cm2

Surface area = 4 × 15.6

= 62.4 cm2

Here is the net of a triangular prism.

What is its surface area?

We can work out the area of each face and write it in the diagram of the net.

10 cm

12 cm

13 cm

20 cm

60 60200

260

260

Then add each area together to get the total surface area

= 60 + 60 + 200 + 260 + 260= 840 cm2

Here is the net of a Surface area of a cylinder

5

3

?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

4cm

3cm

4cm

6cm

4.5m

5m

3m

Triangular Prism

10cm6cm

4cm

5cm

30m

Square Based Pyramid

30m

2m

12m

Cuboid

Cylinder

37m

5m

2m

Cuboids

10cm

5cm

6cm

4cm

6m

3m

4m12m

2m

30cm

30cm

Find the surface area of a ...........

Work out the area of each face.

Your working out will go in here.

Your answer in cm2