Finding three-dimensional shapes
The purpose of this activity is to support students to name common two-dimensional shapes using mathematical terms. Students also explore where in real-life they encounter these shapes.
About this resource
New Zealand Curriculum: 3
Learning Progression Frameworks: Geometric thinking, Signpost 4 to Signpost 5
These activities are intended for students who can recognise and name two-dimensional (flat) shapes. Students should be able to sort two-dimensional shapes into classes using properties like the number of sides and angles, parallel and non-parallel sides, and symmetry. They should understand that some shapes are members of more than one class of shape. For example, the set of squares is included in the set of rectangles.
Finding three-dimensional shapes
Achievement objectives
GM3-3: Classify plane shapes and prisms by their spatial features.
Required materials
- a set of solid shapes, such as relational solids (pictured)
See Materials that come with this resource to download:
- Finding three-dimensional shapes CM (.pdf)
1.
Begin the lesson by allowing students to explore the set of solids.
- What can you tell me about this set of blocks?
- Do you know the mathematical names of the solids?
Students might identify the different shapes, including those that act as the faces of the solid shapes, but may not know the mathematical names.
Shapes like the triangular prism, cylinder, and sphere are likely to be less familiar than the cube and square based pyramid.
2.
Discuss what it means when we say that the shapes are three-dimensional (solid). Draw attention to the two dimensions of flat (planar) shapes like the square and circle: length and width. A cube has an added dimension, height. You might illustrate that by comparing or building a square and a cube (e.g., using card, playdough, or Blu-Tack and toothpicks).
3.
Show the students the pictures in Finding three-dimensional shapes CM.
- For each picture I show you, I want you to find the matching shape in our set.
- How do you know that you have chosen the matching shape?
- What did you look for?
For example, show the picture of the drum and look for students to identify the cylinder as the matching shape.
4.
Students may need prompts to describe the shapes beyond global appearance, as in "they look the same.” To encourage more detailed descriptions, draw students’ attention to features like corners (vertices), edges, faces, and curved surfaces. Progress to property descriptions, such as “The cube has 6 square faces.” You might introduce relevant te reo Māori kupu such as tapa (side/edge), akitu (vertex), and mata (face).
5.
Use your discussion to make a list of the names, features, and property descriptions of the solid shapes.
Cube |
Sphere |
|---|---|
8 corners 12 edges 6 faces that are squares Looks like a die (dice) |
A 3-dimensional circle No corners, edges, or faces Looks like a netball |
6.
Ask students to choose two or three solids.
- Draw (or create) an object you know has that shape.
- Make your drawing as clear as possible.
You might need to do model drawings of some of the solid shapes. Consider providing grid or isometric dot paper, or other building materials (e.g., playdough, Blu-Tack, and toothpicks), or digital tools to aid students in creating their shape drawings. As a precursor to this, you might ask students to identify objects in their immediate environment that match the given shapes.
7.
Provide time for students to share their shape drawings with their peers. As they share, ask the remaining students to find the matching shapes. Ask them to explain their choice by referring to the properties of the solid and matching those properties to the object. For example,
- This is an orange, and it is shaped like a sphere. Any way you look at an orange, it is round, like a circle.
1.
Start with a single, 3-dimensional shape. Focus on similarity and difference.
Find a shape that is the same as this one in some way. Note that the similarity might be:
- faces that are the same shape, such as a cone and cylinder, or a cube and square-based pyramid
- curved surfaces such as a cylinder and a cone
- an apex such as a cone and a pyramid.
Find a shape that is different from this shape in some way. Look for students to explain the difference by attending to properties, such as:
- This shape has triangles for faces, and this shape has squares.
- The shape is curved, and this shape is not.
2.
Look for three-dimensional shapes in the environment. Go on shape hunts around the school or ask students to use digital technology to find images that contain three-dimensional shapes. Make connections between shapes and purpose. For example,
- Rectangular prisms make good boxes because they stack.
- Spheres make good sports balls because they roll and bounce smoothly.
Discuss features and purpose with questions such as:
- How are a cylinder, cone, and sphere different in the way they roll?
- Why are cans the shape of cylinders?
The quality of the images on this page may vary depending on the device you are using.