Introduction to NCERT Class 3 Maths Chapter 2 Toy Joy

Book: Maths Mela, the NCERT Mathematics textbook for Class 3 (Grade 3). Chapter: 2, Toy Joy. Board: CBSE and other schools that follow NCERT. The chapter is about solid shapes. Children make animal and bird faces on boxes, tins and bottles, look at toys built from different shapes and learn to describe what they see. They name the shapes, talk about their faces, edges and corners, build models and join cubes.

What is there in the chapter?

• Craft with old boxes (cubes and cuboids), bottles and tins (cylinders) and cones, and drawing faces on them
• Naming the shapes used in a rocket, a toy engine, houses and other toys, and counting each shape
• Position words: between, on top, under and on
• Talking about faces and edges, which are straight and which are curved, and the note that a cube is a special type of cuboid
• The Construct and Describe game in groups
• Finding cylinders, spheres, cubes, cuboids and cones in the classroom, filling a table and finding which shape is found most and least
• Sorting shapes: no edges, only flat faces, only curved faces, and both flat and curved faces
• Making shapes with clay and sticks and with cubes, and a board game played with a die
• Comparing shapes: how they are the same and how they are different
• The faces of a die and the pattern of the opposite faces
• Joining a cube and a cuboid, joining 3 cubes in different ways and building with six dice

NCERT Class 3 learning objectives for this chapter

These objectives are written from the content of the chapter. They are not copied from the book.

• To recognise and name a cube, a cuboid, a cylinder, a cone and a sphere in objects around us
• To describe a solid by its faces, edges and corners, and to tell flat faces from curved faces
• To sort solids using a property, such as only flat faces or a curved face
• To understand that a cube is a special type of cuboid
• To use position words such as on top, under and between when building and describing a model
• To build models by joining solids and cubes and to count the cubes in a model
• To observe the opposite faces of a die and find the pattern
• To tell how two solids are the same and how they are different

Learning outcomes

After this chapter and the practice on this page a Class 3 child should be able to:

• name a solid shape from a real object, such as a dice, a brick, a tin, a party cap or a ball
• say how many flat faces, curved faces and corners a cube, a cuboid, a cylinder, a cone and a sphere have
• name the solids that have no edges, only flat faces or a curved face
• explain why a cube is also a cuboid
• build a tower from instructions that use on, under and between, and describe a model in words
• count the cubes in a simple model, including hidden cubes
• say that opposite faces on a die add up to 7
• compare two solids and say one way they are the same and one way they are different

Toy Joy Class 3 resources on this page

• Toy Joy Class 3 worksheet: a printable NCERT style worksheet on 3D shapes, their faces and building with shapes.
• Toy Joy Class 3 quiz: a free 20-question online quiz with easy, average and thinking questions, solid pictures, dice and instant marks with a reason for every answer.
• Toy Joy Class 3 activities: 15 free online activities, made of 5 games, 5 workshops and 5 challenges, with marks and a comment after the challenges.
• Practice sheet: 16 questions you can type and check, with a Show answers button.

3D shapes around us

A solid shape takes up space. You can hold it and turn it. A dice, a brick, a tin, an ice-cream cone and a ball are all solid shapes. The chapter uses five of them: the cube, the cuboid, the cylinder, the cone and the sphere. Spotting these shapes in everyday things is the first skill.

Faces, edges and corners

A face is a surface of a solid. A flat face lies flat on a table. A curved face bends round. An edge is where two faces meet. A corner is a point where edges meet. A cube and a cuboid have 12 straight edges and 8 corners. A sphere has no edges and no corners. The book asks which shapes have no edges, which have only flat faces, which have only curved faces and which have both flat and curved faces.

A cube is a special cuboid

A cuboid has 6 flat faces that are rectangles. A cube is a cuboid whose faces are all squares. So every cube is a cuboid, but a cuboid is not always a cube. A brick is a cuboid. A dice is a cube.

Position words

The words on top, under, between, beside and at the bottom tell where a shape is. The book asks which shape is between two others, which is on top of another and which is under another. It also has a Construct and Describe game. One child joins three shapes and describes how, and the others build the same model without seeing it.

Building with solids and cubes

Children build houses, towers and rockets from solids, and make shapes with clay and sticks. They also use cubes. Count the cubes tower by tower and remember the hidden ones. Two cubes joined in a row make a cuboid. The book asks in how many ways 3 cubes can be joined. Try joining them in a straight row and in a bent shape, and see what you get.

Opposite faces on a die

A die has the numbers 1 to 6. Look at the faces that are opposite each other. 1 is opposite 6, 2 is opposite 5 and 3 is opposite 4. In each pair the numbers add up to 7. That is the pattern the book asks children to find.

Comparing shapes

To compare two solids, ask how many flat faces, curved faces and corners each has and what they look like. A cube and a cuboid are the same because both have 6 flat faces and 8 corners. A cylinder and a cone are the same because both have a curved face and a flat round face. They are different because a cone has a corner and a cylinder does not.

Solved examples

Common mistakes

Shapes in daily life

We see solids everywhere. Houses are cuboids, cricket balls are spheres, water tanks and pipes are cylinders and party caps are cones. Ask your child to find five solids at home and name them. Ask which have a curved face and which have only flat faces.

What your child learns from the Toy Joy worksheet

• Naming cubes, cuboids, cylinders, cones and spheres
• Faces, edges and corners
• Flat faces and curved faces
• A cube as a special cuboid
• Position words on, under and between
• Building models and counting cubes
• Opposite faces on a die
• Comparing shapes

Tips for parents and teachers

Use real things, such as boxes, tins, balls and caps. Let your child hold each solid and turn it. Ask them to run a finger along the edges and point to the corners. Play the Construct and Describe game, where one child describes a model and the other builds it. Praise clear descriptions and careful counting.