---
title: "Comparing 2-D and 3-D shapes"
description: "Analyse and compare 2-D and 3-D shapes using informal language to describe sides, vertices, and other attributes"
canonical: https://lightmysky.com/learn/mathematics/comparing-2-d-and-3-d-shapes-mt_yGv8doDAmp
source: https://lightmysky.com/learn/mathematics/comparing-2-d-and-3-d-shapes-mt_yGv8doDAmp.md
retrieved: 2026-09-12
---

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# Comparing 2-D and 3-D shapes

Analyse and compare 2-D and 3-D shapes using informal language to describe sides, vertices, and other attributes

Subject: Mathematics · Area: Geometry · Ages 5 to 6
Page: https://lightmysky.com/learn/mathematics/comparing-2-d-and-3-d-shapes-mt_yGv8doDAmp

## Ready when they can

- Count the sides and corners of a shape
- Compare a triangle and a rectangle by number of sides
- Describe a cube as having 'square faces' and 'corners'

## Lesson: Sides and corners of shapes

Every shape has sides and corners you can count. A side is a straight edge. A corner is where two sides meet.

*(drawing: This triangle has 3 sides and 3 corners.)*

**Example.** A triangle has 3 sides and 3 corners. A rectangle has 4 sides and 4 corners. The rectangle has one more side than the triangle.

Some shapes are not flat. A cube is a solid you can pick up, like a dice. Each flat face of a cube is a square. So each face has 4 straight sides and 4 corners. A cube has sharp corners you can feel with your fingers.

*(drawing: Every flat face on this cube is a square. Count its sides and corners the same way: 4 and 4.)*

**Recap.** Count sides and corners to tell shapes apart.

## Practice

18 questions on this page, each with its working shown.

## Needs first

- [2-D shapes](https://lightmysky.com/learn/mathematics/2-d-shapes-mt_KJeEeTutJI)
- [3-D shapes](https://lightmysky.com/learn/mathematics/3-d-shapes-mt_Qcp2d_kuta)

## Opens up

- [Building & Drawing Shapes](https://lightmysky.com/learn/mathematics/building-and-drawing-shapes-mt_2VR963szuk)
- [Defining attributes of shapes](https://lightmysky.com/learn/mathematics/defining-attributes-of-shapes-mt_bfhng6mOuy)
- [Edges, vertices, and faces](https://lightmysky.com/learn/mathematics/edges-vertices-and-faces-mt_Mnodea7mG_)
- [2-D shapes (age 6+)](https://lightmysky.com/learn/mathematics/2-d-shapes-age-6-mt_sBcRdUfAzV)
- [Combining Simple Shapes](https://lightmysky.com/learn/mathematics/combining-simple-shapes-mt_XjwUlmxdCT)