Thread Academy

Flat Shapes

Name and describe circles, triangles, rectangles and squares.

  • Define and explain Flat Shapes in your own words
  • Use key terms such as Side accurately
  • Apply what you have learned to new examples and questions
  • Avoid the common mistakes learners make with this topic

Shapes are everywhere — in wheels, windows and footballs. Measures let us describe how long, how heavy and how full things are.

This lesson focuses on Flat Shapes: name and describe circles, triangles, rectangles and squares.

Definition: Flat Shapes

Name and describe circles, triangles, rectangles and squares.

Key ideas

Shapes have properties

Counting sides and corners tells shapes apart: a triangle has 3 sides and 3 corners, a square has 4 equal sides. Properties are more reliable than looks.

Comparing measures

Words like longer, heavier and holds more only make sense when you compare two things directly — always name both sides of the comparison.

Key term — Side: A straight edge of a flat shape. A square has four equal sides.

Sorting the toy box

A toy box holds 12 triangles, 8 squares and 5 circles. How many more triangles than squares are there, and what is the total of all three shapes?

More triangles than squares: 12 − 8 = 4. Total shapes: 12 + 8 + 5 = 25.

Answer: 4 more triangles; 25 shapes altogether.

Common mistakes
  • Calling every four-sided shape a square A square needs four equal sides and four right angles; a rectangle has opposite sides equal instead.
  • Reading the wrong end of the ruler Always start measuring from the 0 mark, not from the end of the ruler.

Practice

Name the solid with 6 square faces.
Picture a dice.

A cube.

How many sides does a hexagon have?
Think of the prefix hex-.

6 — a hexagon has six sides and six vertices.

Which is longer: 1 metre or 90 centimetres?
How many centimetres are in a metre?

1 metre — it equals 100 cm, which is more than 90 cm.

A jug holds 500 ml. You pour in 250 ml. How much more can it hold?
Subtract what is already in the jug.

250 ml — 500 − 250 = 250.

Quick check

Flat Shapes — quick check

Which of these best defines "Side"?

A straight edge of a flat shape. A square has four equal sides.

A ribbon is 45 cm long. 15 cm is cut off. How long is left?

30 cm — 45 − 15 = 30.

Order these by weight, lightest first: an apple, a bag of flour, a grape.

Grape, apple, bag of flour — from lightest to heaviest.
Key takeaways
  • Flat Shapes: name and describe circles, triangles, rectangles and squares.
  • Shapes have properties: Counting sides and corners tells shapes apart: a triangle has 3 sides and 3 corners, a square has 4 equal sides.
  • Symmetry: When one half of a shape mirrors the other half, like a butterfly's wings.
  • Watch out for: calling every four-sided shape a square
Solid Shapes →Back to Grade 7 chaptersRelated resources →