Naming 2D shapes

What is this skill?

In kindergarten, children learn to name common flat shapes: circles, squares, triangles, rectangles and hexagons. The goal is to recognize each shape whatever its size or position, so a triangle is still a triangle when it is tiny, enormous, upside down or tilted.

Children start to notice what makes each shape what it is. A triangle has three straight sides; a square has four equal sides; a rectangle has four sides with opposite sides equal; a hexagon has six sides; a circle is round with no straight sides or corners. In kindergarten the names come first, and counting sides and corners is explored more fully in first grade.

Why it matters

Geometry is a part of math that many children find enjoyable, and it builds visual reasoning that helps later with fractions, area and measurement. Recognizing shapes by their properties, rather than by a single picture in a book, is an early form of mathematical definition: a shape belongs to a group because of its features.

Shape names are also everyday vocabulary. Being able to say "the hexagon-shaped tile" or "the rectangle button" helps children describe the world precisely. In first grade, children build on these names by counting sides and corners, and by putting shapes together to make new ones.

Common mistakes

• Only recognizing a shape in its "usual" position. Many children say a triangle standing on its point is not a triangle, or call a tilted square a diamond. Turning shapes around while naming them helps.
• Thinking that squares are not rectangles, or calling every rectangle a square. In kindergarten, it is enough to notice that a square has all four sides the same length.
• Calling any round-ish shape a circle, including ovals. Comparing a circle and an oval side by side helps children see the difference.

How to help at home

• Go on a shape hunt around the house or the street: clocks and plates (circles), doors and books (rectangles), stop signs (octagons, a bonus shape), and honeycomb pictures (hexagons).
• Cut shapes out of paper or card in different sizes, then turn them upside down and sideways and ask your child to name each one.
• Build shapes with sticks, straws or pasta. Ask how many sticks a triangle needs and how many a square needs. Then try to build a triangle with four sticks and talk about why it does not work.
• Play "I spy" with shapes: "I spy something shaped like a rectangle on the wall." Let your child take a turn giving the clues.

Worked examples

These are real questions from the Tutorsaurus naming 2d shapes practice, with the answers worked out.

1. Example 1

   Tap the triangle.

   Choices: square, rectangle, circle, triangle

   Answer: triangle. The triangle has 3 sides.

2. Example 2

   Tap the hexagon.

   Choices: rectangle, hexagon, triangle, circle

   Answer: hexagon. The hexagon has 6 sides.

3. Example 3

   What shape is this?

   Choices: square, hexagon, circle, rectangle

   Answer: square. This is a square. A square has 4 sides.