1. SHAPE AND SPACE Senior Maths

2. Shape and space – 2D Shapes Children need to know Names of 2D shapes Definition of a polygon: a 2D shape bordered by straight lines which has the same number of sides as it has angles Examples of polygons: triangle, quadrilateral,pentagon, hexagon,heptagon,octagon,nonagon,decagon Properties, number of sides, number of congruent sides, number and types of angle, sum of angles (divide into triangles)

3. The Joy of Triangles! 3 types of triangle: equilateral, isoceles and scalene, type dependent on number of congruent sides and angles! 3 equal sides, 2 equal angles = equilateral 2 equal sides, 2 equal angles = isoceles 0 equal sides, 0 equal angles = scalene Right angled triangle a special case, can be scalene or isoceles but never equilateral Angles in a triangle always add up to 180  To find the missing angle in a triangle, add the 2 given angles and subtract from 180  Children should be able to construct a triangle given the length of 2 sides and one angle. Children should be able to calculate the sum of the angles in any polygon by dividing it into triangles. Discuss practical use of triangles e.g. in roof struts.

4. Other 2D shapes Children will need to know names and properties of polygons from 4 – 10 sides Will need to know: number and types of angles, number of sides, number of parallel sides, number of equal sides.

5. Lines and angles Definitions of lines: vertical, horizontal, diagonal (oblique) parallel and perpendicular – last 2 terms present difficulty. Vertical Horizontal Diagonal Parallel Perpendicular

6. Types of angles

7. Measuring and constructing angles This is a BIG problem for a lot of kids! Introducing …the protractor!

8. The Protractor A major cause of confusion is which line of figures to use. We explain it as follows: The line of figures you use depends on (a) whether you measure from the right or the left or (b) whether you’re measuring an obtuse or acute angle. Here’s a useful link: http://www.mathplayground.com/measuringangles. html http://www.mathplayground.com/measuringangles. html

9. 3D Shapes With 3D shapes, the major issues are: Number of faces Number of edges Number of vertices Identification of shapes Identification and construction of nets

10. Example Look at the net below. What 3D shape does it represent?

11. Example (2) Identify this shape: How many faces has it? How many edges has it? How many vertices has it? Will it stack neatly with other shapes of the same type?

12. Rotations This is an area which causes frequent problems. It requires a specialised skill – spatial ability. Here’s an example: Rotate this shape 90  clockwise. (a) (b)