Faces, edges and vertices of 3-D shapes: what children learn
In this game children match each 3-D shape to its properties, such as 6 square faces, 12 edges and 8 vertices for a cube. Several shapes have similar numbers, so children must know each shape well rather than guess.
Supports part of Common Core 2.G.A.1, which mentions faces of solid shapes. Counting edges and vertices goes a little beyond it.
Common Core connection: 2.G.A.1. This is focused practice for part of the standard.
How to play
Pick a card on the left, then the card on the right that matches it. Each game has 6 pairs. Wrong matches are counted as mistakes, and you get three stars for a game with no mistakes.
Step by step
- Faces. Count every surface. A cube has 6 faces: top, bottom, front, back, left and right.
- Edges. An edge is a line where two faces meet. Run a finger along each edge to count them. A cube has 12.
- Vertices. A vertex is a corner, where edges meet. A cube has 8: 4 on top and 4 underneath.
- Curved surfaces. A cylinder has 2 flat circle faces and 1 curved surface. In elementary school we usually count the curved surface as a face, so a cylinder has 3 faces, 2 edges and no vertices.
Worked examples
Example 1: How many faces, edges and vertices does a square-based pyramid have?
Working: 1 square base and 4 triangles; 4 edges round the base and 4 up to the top; 4 base corners and 1 at the top.
Answer: 5 faces, 8 edges and 5 vertices
Example 2: Which shape has 5 faces, 9 edges and 6 vertices?
Working: Two triangle ends and three rectangle faces.
Answer: triangular prism
Example 3: Which shape has 1 curved face, no edges and no vertices?
Working: Round all over.
Answer: sphere
Common mistakes and how to fix them
- Counting only the faces you can see in a picture. Hold a real shape and turn it over, or mark each face with a sticker.
- Mixing up edges and vertices. Edges are lines; vertices are points. Run a finger along an edge and tap a vertex.
- Thinking a cuboid and a cube have different numbers of faces. Both have 6 faces, 12 edges and 8 vertices. The difference is the shape of the faces.
Activities to try at home
- Look at a cereal box and count its faces, edges and vertices together.
- Build 3-D shapes with straws and modelling clay; the clay balls are the vertices.
- Describe a 3-D shape for someone else to guess.
Ideas for the classroom
- Students put a sticker on each vertex and a dot on each face of real 3-D shapes.
- Fill in a table of faces, edges and vertices for a set of shapes.
- Play 'Guess my shape' using only properties.
Free printable game and worksheet
The free printable starts with a game sheet, such as a color-by-answer picture, an answer maze or a secret-code joke, followed by a worksheet. Both use the same checked questions as the online game, and the answers are on the last page. Print it, or save it as a PDF from your browser’s print menu.
Open the free printable game and worksheet
Frequently asked questions
How should I choose this game for my learner?
Supports part of Common Core 2.G.A.1, which mentions faces of solid shapes. Counting edges and vertices goes a little beyond it.
Is a curved surface a face?
In elementary school a curved surface is usually counted as a face, which is what this game does. Some secondary textbooks count only flat faces.
What is the plural of vertex?
Vertices. One vertex, two vertices.
Can it be played with a keyboard?
Yes. Tab to a card, press Enter to pick it, then pick its partner.