This one comes courtesy of commenter jono, who pointed out the absence of quadrilaterals in the f-6 part of the new Curriculum. jono noted that the terms “rhombus” and “kite” and “parallelogram” and Trapezium” are not once mentioned, and that the single mention of “quadrilateral” is in a Year 1 Space elaboration:
make, compare and classify familiar shapes; recognise familiar shapes and objects in the environment, identifying the similarities and differences between them (AC9M1SP01)
classifying a collection of shapes, including different circles, ovals, regular and irregular shapes, triangles and quadrilaterals, saying what is the same about the shapes in a group and what is different between the groups
The elaboration does not clearly suggest that students should learn the word “quadrilateral” and, in Year 1, presumably they would not. In any case, elaborations are optional. Thus, according to the new Curriculum, primary students need not be exposed to, much less remember, the term “quadrilateral” or the terms for any types of quadrilaterals other than rectangles and squares.
The following list comprises all F-6 content descriptors and elaborations that we could find which have anything even remotely to do with the naming or classifying of quadrilaterals beyond squares and rectangles.
recognise, compare and classify shapes, referencing the number of sides and using spatial terms such as “opposite”, “parallel”, “curved” and “straight” (AC9M2SP01)
sorting a collection of shapes in different ways based on their features such as number of sides, whether all sides are equal, whether pairs of opposite sides are parallel; for example, collections of triangles and other polygons
compare the parallel cross-sections of objects and recognise their relationships to right prisms (AC9M6SP01)
understanding that right prisms are objects where parallel cross-sections perpendicular to the base of the prism are the same shape and size
connecting different right prisms to the shape of their parallel cross-sections, such as a triangular prism which can be described as a stack of the same sized triangles, and a cube or square prism, which can be described as a stack of the same sized squares
locate points in the 4 quadrants of a Cartesian plane; describe changes to the coordinates when a point is moved to a different position in the plane (AC9M6SP02)
using the Cartesian plane to draw lines and polygons, listing co-ordinates in the correct order to complete a polygon
It is a large gap… but the classification of quadrilaterals does finally appear in year 7: AC9M7SP02
Which also hints at the triangle inequality and constructing triangles with given properties.
I wish we had more classical constructions in the curriculum – it helps to make sense of triangle congruence/similarity rules (SSS, SAS, AAS, and not ASS!). At least circle theorems survive in the year 10 optional content.
Circle theorems have survived in about the same sense as factoring of numbers survived the Roman empire.