MATHEMATICS 3D Shapes

Aims of the Lesson To identify the 4 main categories of 3D shapes. To recognise prisms, learn to given them their full mathematical name and recognise their nets. To recognise and pyramids, learn to give them their full mathematical name and recognise their nets. To recognise and polyhedra, learn to give them their full mathematical name and recognise their nets. To recognise circular 3D shapes, learn their correct mathematical names and recognise their nets.

PRISMS The end (or base) shape of a prism gives it its name All the other faces are RECTANGLES (Remember this when working on nets!)

Example 1 To draw: End shape first Parallel lines of equal length from each corner Join the ends of the parallel lines The above is a TRIANGULAR PRISM

Example 2 To draw: End shape first Parallel lines of equal length from each corner Join the ends of the parallel lines The above is a RECTANGULAR PRISM otherwise known as a CUBOID

Prism NETs The NET of a triangular prism The NET of a hexagonal prism

PYRAMIDS The base shape of the pyramid gives it its name All the other faces are TRIANGLES (Remember this when working on nets!)

Example 1 To draw: Base shape first (flat) Choose a position for the top point of the pyramid Join each of the base’s vertices to the top point of the pyramid The above is a TRIANGLE-BASED PYRAMID otherwise known as a TETRAHEDRON

Example 2 To draw: Base shape first (flat) Choose a position for the top point of the pyramid Join each of the base’s vertices to the top point of the pyramid The above is a SQUARE-BASED PYRAMID

Pyramid NETs The NET of a square- based pyramid The net of a hexagon- based pyramid

POLYHEDRA ‘Poly’ means many and ‘hedron’ means face, so a polyhedron is a 3D shape with many faces (Technically all prisms and pyramids are also polyhedra) Proper polyhedra just have triangular faces (Remember this when working on nets!)

Example 1 To draw: Middle shape first A point above and below Join each vertex of the middle shape to each point The above is an OCTAHEDRON

NET This is the net of an octahedron

CIRCULAR 3D Shapes Sphere (or polyhedron with 1 face) Cone (or circle-based pyramid) Cylinder (or circular prism)

CIRCULAR 3D Shapes NET of a sphere: Sphere (or polyhedron with 1 face)

CIRCULAR 3D Shapes NET of a cylinder Cylinder (or circular prism)

CIRCULAR 3D Shapes NET of a cone Cone (or circle-based pyramid)

What next? Print out the notes called Shape2. Read through them and make sure you answer any questions. Work through the MyMaths lesson and its online homework called: Shape > 2D and 3D Shapes > 3D Shapes found at: Work through the MyMaths lesson and its online homework called: Shape > 2D and 3D Shapes > Nets of 3D Shapes found at: Now move on to the Shape3 powerpoint