Teacher notes

• Revise with students the names of shapes from Level 1 for example. triangles, squares, rectangles. At Level 2 students are extending their mathematical vocabulary to include the names of other polygons which may be less familiar, such as quadrilaterals, pentagons, hexagons, and octagons, and the adjectives frequently used to describe them.
  Teachers can support student’s learning of new vocabulary by accepting student’s own labels or descriptions, while also modelling and encouraging the use of more specific geometrical vocabulary. Emphasising geometric features such as the length of sides or number of corners, rather than aspects such as colour, will help students make links to what they already know and develop new vocabulary without explicitly practising it.
• Encourage students to describe shapes using more than one feature. For example, closed shape with straight sides; equal sides and corners. Introduce synonyms (e.g. thin / narrow), particularly with students who have limited vocabularies or for whom English is not their first language.
• Initially students may get the names of polygons confused. Discussing related words or pictures with links to the number of sides, (such as tricycle, triplets, quad bike, pentathlon, octopus), may help students correctly label shapes.
• Sometimes other features such as orientation, colour, texture, size etc., can confuse students so they fail to recognize, for example, a triangle. It is very important that students at Level 2 are exposed to shapes in real objects, irregular polygons, and different orientations of 2-D shapes (for example an upside-down trianglular sign resting on a corner rather than on its base), and discuss the features that ALL triangles etc., have in common. A selection of regular and irregular shapes is available on this Printable Master Rich task 1 - Question 1 - 2-D shapes.
• Polygons are an important category to which many 2-D shape belong. To be a polygon a shape must:
  • be 2-D
  • be closed (i.e. the sides of the polygon all meet without gaps)
  • have only straight sides.

For example, circles and ovals are not polygons because they have curved sides.

• We have chosen to use ‘rectangle’ rather than ‘oblong’ with this age group. Oblongs have four corners of equal size (90º) and one pair of equal opposite sides, therefore the category does not include squares, while rectangles does.
• A rhombus is a flat shape with 4 straight sides of equal length. Opposite sides are parallel and opposite angles are equal. The plural form of rhombus can be either rhombi or rhombuses. In the Level 2 books we will consistently use rhombuses.
• Use dotty paper for drawing 1 cm square dotty paper or photograph geoboards to support students with poor visual and spatial ability in the Practical, Sides and corners, on page 239 of the Student Resource Book. Students could bring their pictures of the geoboard shapes they made to a larger group or whole class discussion and gain a better perception of the diversity of shape possible for each polygon.
• Students’, What shape am I? puzzles (from page 240 of the Student Resource Book) could be collated into a class ‘book’ or digital presentation with the answers to each question on a subsequent page/slide.