Knowing key shapes is a confidence-boost

by | Mar 21, 2016 | Exams, Maths, Teach, Uncategorized | 0 comments

Getting properly familiar with 2D and 3D shapes is easy as anything when there is a little set of them sitting on the kitchen table at home.

Picking up shapes, comparing them with each other and getting familiar with their names is a simple, relatively fun thing to do together. It will give your child a real boost if shapes come up at school, or in an exam, and they happily know which is which and what is what.

What’s great about the topic of  shape is that there are no calculations involved – certainly not at this stage – and so learning their names and properties is just a practical, manageable activity.

Trawling the internet for a great set of shapes isn’t easy – as they tend to be geared towards younger children. But here are two options worth investing in:

2D shapes

3D shapes

Here is how to get the best out of your shape sets:

  • Point out that the 2D shapes in the set are mostly ‘regular’, meaning all their angles and sides are the same. Any 2D shape with 6 straight sides is called a hexagon, or 5 straight sides is called a pentagon,  and they don’t need to be regular.
  • In this set there is an irregular hexagon that is labelled a ‘chevron’. You would be expected to call it a hexagon in a test.
  • Look how easy it is to mix up the scalene and the equilateral triangles. Consider the differences.
  • Isosceles triangles can be tall and thin or low and wide. Consider that these are simply examples of key shapes and the rule of the shape, i.e. 2 pairs of equal sides and angles, is more important than the look of it.
  • Trapeziums have 4 straight sides with only one pair that are parallel. Consider how differently they can look and still be trapeziums. The rule is key.
  • The proper name for the oval is ‘ellipse’.
  • Use mathematical vocabulary (straight sides, regular/irregular shapes, equal angles, right angle, parallel sides, perpendicular, quadrilateral, vertical, horizontal).

 

  • Separate the pyramids from the prisms and consider how easy they are to mix up by accident. Particularly if the triangular prism is shortened. 
  • Discuss how coins are solid shapes and any shape with a thickness to it is 3 dimensional. With that in mind, they mustn’t be confused by coins – a 5p piece is a cylinder in the same way that a loo roll is too. Consider how different each shape would look when skinny. This is how examiners trick those who don’t know the rules…
  • Use mathematical vocabulary (how many faces, vertices, edges) as most questions will use these terms.

 

Keep the 2D chat separate from the 3D chat – only putting out one set of shapes for a week or so, before changing it for the other.