---
title: "Sorting 2-D and 3-D shapes"
description: "Compare and sort common 2-D and 3-D shapes and everyday objects by their properties"
canonical: https://lightmysky.com/learn/mathematics/sorting-2-d-and-3-d-shapes-mt_fEuoBYw6bU
source: https://lightmysky.com/learn/mathematics/sorting-2-d-and-3-d-shapes-mt_fEuoBYw6bU.md
retrieved: 2026-10-19
---

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# Sorting 2-D and 3-D shapes

Compare and sort common 2-D and 3-D shapes and everyday objects by their properties

Subject: Mathematics · Area: Geometry · Ages 6 to 7
Page: https://lightmysky.com/learn/mathematics/sorting-2-d-and-3-d-shapes-mt_fEuoBYw6bU

## Ready when they can

- Sort a collection of 2-D shapes by number of sides
- Sort 3-D shapes by number of faces or whether faces are flat/curved
- Explain criteria used to sort a group of shapes

## Lesson: Sorting shapes into groups

Sorting means putting things into groups because they share something. You already know that flat shapes have sides and corners, and solid shapes have faces. To sort shapes, pick one thing to check, like the number of sides or the number of faces, then put the shapes with the same answer together.

*(drawing: This triangle has 3 straight sides, so it goes in the 3-sides group.)*

**Example.** Leo has a bag of flat shapes: two circles, three triangles, and two squares. He sorts them by counting sides. Circles have no straight sides, so they go in one pile. Triangles have 3 sides, so they go in another. Squares have 4 sides, so they get their own pile too.

**Example.** Now think about solid shapes. A cube has 6 faces, and every face is flat, so it goes in the flat-faces group. A ball is curved all over and has no flat faces at all, so it goes in the curved group. A can has 2 flat faces on its ends and a curved side around the middle, so it has both kinds.

**Tip.** When you sort shapes, say your rule out loud, like 'these all have 4 sides.' That way anyone can check your groups and get the same answer.

**Recap.** Pick one thing shapes share, like sides or faces, then group them by that rule.

## Practice

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

## Needs first

- [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)

## Opens up

- [Classifying shapes by line properties](https://lightmysky.com/learn/mathematics/classifying-shapes-by-line-properties-mt_r8c43QB6wx)