Class 5 Maths Chapter 9 Boxes and Sketches – Complete Notes

📦 Chapter 9 – Boxes and Sketches

Class: 5 (CBSE)
Subject: Mathematics
Main Ideas: Nets, Cubes, Open Boxes, Floor Maps, Deep Drawings, Views

📘 Introduction

In this chapter we learn how 3-dimensional (3D) objects like boxes and cubes can be shown on paper using 2-dimensional (2D) drawings.

This chapter improves our ability to visualise shapes and understand how objects look when folded, opened, or seen from different sides.

🍬 Sweet Box – Net of a Box

Ramya bought sweets packed in a box made from a paper cut-out. When the box was unfolded, it became a flat shape called a net.

✔ What is a Net?

A net is a flat shape which can be folded to make a 3D object.

Not all nets can be folded into a box. The faces must meet properly.

🧊 Shapes that Fold into a Cube

A cube has:

Faces = $6$
Edges = $12$
Vertices = $8$

All faces of a cube are squares.

If the side of each face is $s$, Area of one face = $s^2$ Total surface area = $6 \\times s^2$

📐 Which Nets Make a Cube?

Only some arrangements of $6$ squares can fold into a cube. If faces overlap or do not meet correctly, the shape will not form a cube.

Activity:
Draw different nets using $6$ squares and test which ones fold into a cube.

📦 Shapes for an Open Box

An open box is a box without a top.

An open box made from $5$ squares has:

$1$ base
$4$ sides

Some shapes with $5$ squares can fold into an open box, while others cannot.

📦 Boxes and Boxes (Not All Boxes Are Cubes)

Different nets fold into different boxes such as:

Cuboid
Cylinder-like boxes
Triangular boxes

A cube is a special box where all faces are equal squares.

🏠 Floor Maps

A floor map shows the layout of a house from the top. It shows:

Position of rooms
Doors
Windows

Floor maps do NOT show height. They only show length and width.

🏡 Deep Drawings (3D Drawings)

To show length, width, and height, we use deep drawings.

A deep drawing is also called a 3D perspective drawing.

Deep drawings help us imagine how a building or box really looks.

🧊 A Simple Way to Draw a Cube

Steps:

Draw two squares slightly apart
Join the corresponding corners

This shows depth and makes the cube look 3-dimensional.

🎲 Deep Drawing Puzzle

When a cube net with dots is folded, only certain deep drawings will match correctly.

Correct deep drawings must keep:

Face positions
Adjacent faces

the same as the net.

📦 Matchbox Play – Views of Objects

A bridge made of matchboxes looks different from different sides.

✔ Three Important Views

View	What it Shows
Top View	Length and width
Front View	Length and height
Side View	Width and height

One view alone is not enough to understand the full shape.

🧠 Visualisation Skill

Understanding boxes and sketches improves our ability to:

Imagine folded shapes
Read drawings correctly
Solve geometry problems easily

✍️ Practice Questions

1) What is a net?

2) How many faces does a cube have?

3) Can every net of $6$ squares make a cube? Why?

4) What is the difference between a floor map and a deep drawing?

5) If the side of a cube is $3$ cm, find the area of one face and total surface area.

✅ Quick Revision

✔ Nets are flat shapes of 3D objects
✔ Cube has $6$ square faces
✔ Open boxes have no top
✔ Floor maps show top view only
✔ Deep drawings show height, width, and length

🎉 Chapter Complete

After studying this chapter, students can confidently identify correct nets, draw cubes, read floor maps, understand deep drawings, and visualise 3D objects.

Class 5 Maths Worksheet – Boxes and Sketches

📝 Complete Worksheet – Boxes and Sketches

Class: 5 (CBSE)
Chapter: Boxes and Sketches
Main Topics: Nets, Cubes, Open Boxes, Floor Maps, Deep Drawings, Views 🎯

Section A – Multiple Choice Questions (MCQs)

Q1. A net is:

(a) A 3D object

(b) A flat shape that can be folded into a 3D object

(d) A floor map

Q2. How many faces does a cube have?

(a) $4$

(b) $5$

(d) $8$

Q3. Which shape can be folded to make a cube?

(a) Any shape of $6$ squares

(b) Only some arrangements of $6$ squares

(d) A rectangle

Q4. If the side of a cube is $s$, the area of one face is:

(a) $4s$

(b) $s^2$

(d) $2s^2$

✔ Q1 → (b) A flat shape that can be folded into a 3D object
✔ Q2 → (c) $6$
✔ Q3 → (b) Only some arrangements of $6$ squares
✔ Q4 → (b) $s^2$

Section B – Fill in the Blanks

1) A cube has __________ edges.

2) An open box does not have a __________.

3) A floor map shows the __________ view of a place.

4) Total surface area of a cube is given by __________.

✔ $12$
✔ top
✔ top
✔ $6s^2$

Section C – Very Short Answer Questions

1) What is a cube?

2) What is a net?

3) How many vertices does a cube have?

✔ A cube is a solid shape with $6$ square faces.
✔ A flat shape that can be folded to make a 3D object.
✔ $8$

Section D – Short Answer Questions

Q1. Can every net of $6$ squares form a cube? Explain.

Q2. What is the difference between a floor map and a deep drawing?

Q3. Write the formula for the total surface area of a cube.

✔ No, only some arrangements fold correctly without overlapping.
✔ Floor map shows top view only, deep drawing shows length, width and height.
✔ $6s^2$

Section E – Long Answer Questions

Q1. Explain what is meant by top view, front view and side view.

Q2. If the side of a cube is $4$ cm, find:

Area of one face
Total surface area

✔ Top view shows length & width, front view shows length & height, side view shows width & height.
✔ Area of one face = $4^2 = 16 \text{ cm}^2$
✔ Total surface area = $6 \\times 4^2 = 96 \text{ cm}^2$

Section F – HOTS / Thinking Questions ⭐

Q1. If the side of a cube becomes $2$ times, how many times does its total surface area increase?

Q2. Why is one view not enough to understand a 3D object completely?

✔ Surface area becomes $2^2 = 4$ times.
✔ Because a single view cannot show all dimensions.

🎯 Worksheet Complete

✔ Practice visualising nets daily
✔ Revise cube properties carefully
✔ Compare floor maps and deep drawings
✔ You are now **exam-ready** ✅