The Great Pyramid of Khufu is 147m from the ground to the top and each side of the base is 230m long. The Egyptians positioned the sides of the pyramid facing north, south, east and west. They did not have compasses so archaeologists believe that they used the stars as a guide. They used the circumpolar stars that circle the North Pole of the Earth. The ancient Egyptians also used a cubit rod to measure out the sides of the pyramid.

First broadcast:
19 October 2007

Challenge pupils to calculate the area of the Great Pyramid's base, using the measurements given at the start of the clip. Can the children also work out the volume of the pyramid? Pupils could build pyramid shapes from interlocking plastic cubes. If the tip of their pyramid is a square made up of four cubes, how many cubes will be needed to make the layer immediately below? And the layer below that? The children could go on to calculate how many cubes would be needed to build a one-metre-high model of a pyramid. As a homework activity, pupils could look for circumpolar stars in the night sky (the Great Bear and Little Bear constellations are visible all year round from the UK). The Ancient Egyptians used circumpolar stars to align the Great Pyramid with the north.