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