Put the instructions in order to construct this shape. Constructions GM1.3 Core Starter Put the instructions in order to construct this shape. A Draw a vertical line with a ruler through the middle of the circle. B Measure and mark two points on the line 2 cm from the circumference. C Rub out vertical line and centre marks. D Set compass to 2 cm. E Draw another semicircle to the right around the upper 2 cm mark. F Mark a point in pencil and draw a circle around that point with the compasses. G Draw semicircle to the left around the lower 2 cm mark. H Set a pair of compasses to a radius of 4 cm. Preamble An opportunity to practise skills with ruler and compasses, this activity is an attempt to show pupils the importance of an ordered approach to constructions. However attention should be drawn to the fact that C (rubbing out construction lines) is not a good idea in any formal assessment situation. Pupils should be given the opportunity to follow their ordered instructions to see if they work. As an extension activity, pupils could be asked how the instructions would change if, for example, the radius of the large circle were increased to 5 cm. Possible content Constructions with ruler and compasses. Resources Ruler and compasses. Some pupils may benefit from having the steps copied onto cards for them to rearrange. Solution/Notes The correct order is: H F A B D G E C Original Material © Cambridge University Press 2009 Original Material © Cambridge University Press 2009