Chapter 12 of 12
Chapter 12: Our Earth and the Sky
Sun, Moon, Stars, Mountains, Rivers and Saving Nature | CBSE Session 2026–27
Core Pedagogical Competencies & Concepts
- Earth as Our Home (Land, Water, Atmosphere)
- Landforms: Plains, Mountains, Hills, Valleys, Deserts
- The Day Sky (Sun, Clouds) and Night Sky (Moon, Stars)
- Environmental Protection (Planting Trees, Saving Nature)
All Textbook Exercises & In-Text Tasks (15 Questions)
100% Complete Ingestion
Q1
Think and Tell
What is Earth? Why is it unique in the solar system?
[3 Marks]
✅ Step-by-Step Solution & Working
Earth is the third planet from the Sun and the home of all living beings. It is unique because it is the only known planet that has liquid water, air with oxygen, and an optimal temperature suitable for life.
CBSE Step-by-Step Marking Scheme
Third planet and home of living things
1
Presence of water and oxygen
1
Suitable temperature for life
1
Q2
Landforms on Earth
Differentiate between Plains, Hills, and Mountains.
[3 Marks]
✅ Step-by-Step Solution & Working
• Plains: Flat, level land where most people live, build cities, and grow crops.
• Hills: High raised land with a cooler climate.
• Mountains: Very tall, rocky land with sharp peaks, often covered with snow (e.g., Himalayas).
CBSE Step-by-Step Marking Scheme
Plains definition
1
Hills definition
1
Mountains definition with peak/snow
1
Q3
Valleys and Rivers
What is a 'Valley'? Where do rivers originate?
[2 Marks]
✅ Step-by-Step Solution & Working
A low land between two hills or mountains is called a 'Valley'. Rivers originate from melting snow glaciers on high mountains or from natural springs.
CBSE Step-by-Step Marking Scheme
Low land between hills/mountains
1
Originate from melting glaciers/springs
1
Q4
Deserts
What is a desert? Name one plant and one animal adapted to desert life.
[3 Marks]
✅ Step-by-Step Solution & Working
A desert is a large, dry area of land covered with sand that receives very little rainfall.
• Desert Plant: Cactus
• Desert Animal: Camel.
CBSE Step-by-Step Marking Scheme
Desert definition
1
Cactus plant
1
Camel animal
1
Q5
The Sun
What is the Sun? Why is life impossible without the Sun?
[3 Marks]
✅ Step-by-Step Solution & Working
The Sun is a huge, glowing ball of hot gases and our closest star. Life is impossible without it because it provides light and heat; without the Sun, Earth would be a frozen, pitch-black ball where no plant could grow.
CBSE Step-by-Step Marking Scheme
Huge glowing star / ball of gases
1
Provides light and heat
1
Plants need sunlight to grow
1
Q6
The Moon and its Shapes
Does the Moon have its own light? Why does its shape appear to change every night?
[2 Marks]
✅ Step-by-Step Solution & Working
No, the Moon does not have its own light; it shines by reflecting sunlight. Its shape appears to change every night (Phases of the Moon) as it orbits around the Earth and we see different illuminated portions.
CBSE Step-by-Step Marking Scheme
Reflects sunlight
1
Orbits Earth creating phases
1
Q7
The Stars
Why do stars look like tiny twinkling dots in the night sky?
[2 Marks]
✅ Step-by-Step Solution & Working
Stars are huge glowing fireballs just like our Sun, but they look like tiny dots because they are located millions of kilometers far away from Earth.
CBSE Step-by-Step Marking Scheme
Huge fireballs like the Sun
1
Located extremely far away
1
Q8
Match the Following
Match the natural feature with its description:
(a) Flat land -> (i) Desert
(b) High rocky land with snow -> (ii) Valley
(c) Sandy dry region -> (iii) Plain
(d) Low land between hills -> (iv) Mountain
[2 Marks]
✅ Step-by-Step Solution & Working
(a) Flat land -> (iii) Plain
(b) High rocky land with snow -> (iv) Mountain
(c) Sandy dry region -> (i) Desert
(d) Low land between hills -> (ii) Valley.
CBSE Step-by-Step Marking Scheme
All 4 correct matches
2
Q9
True or False
State True or False:
(a) The Sun rises in the East and sets in the West.
(b) There is no air or liquid water on the Moon.
(c) Cutting down trees helps to keep the Earth cool and green.
[3 Marks]
✅ Step-by-Step Solution & Working
(a) True
(b) True
(c) False (Cutting trees causes global warming and pollution).
CBSE Step-by-Step Marking Scheme
1 mark per correct answer
3
Q10
Fill in the Blanks
Fill in the blanks:
(a) The model of the Earth is called a ________ (globe / map).
(b) The Earth takes ________ (24 hours / 365 days) to complete one rotation on its axis.
(c) We celebrate Earth Day on ________ (22nd April / 5th June).
[3 Marks]
✅ Step-by-Step Solution & Working
(a) globe
(b) 24 hours
(c) 22nd April.
CBSE Step-by-Step Marking Scheme
1 mark per correct blank
3
Q11
Day and Night Formation
How are day and night caused on Earth?
[2 Marks]
✅ Step-by-Step Solution & Working
The Earth spins continuously on its axis like a top. The side of the Earth facing the Sun experiences Day, while the side turned away in darkness experiences Night.
CBSE Step-by-Step Marking Scheme
Earth's rotation on axis
1
Facing Sun = Day; Facing away = Night
1
Q12
Atmosphere
What is the blanket of air surrounding the Earth called?
[1 Marks]
✅ Step-by-Step Solution & Working
The blanket of air surrounding the Earth is called the 'Atmosphere'.
CBSE Step-by-Step Marking Scheme
Atmosphere
1
Q13
Saving Mother Earth
Mention three promises you can make to protect Mother Earth.
[3 Marks]
✅ Step-by-Step Solution & Working
Three eco-promises:
1. Plant at least one sapling every year on my birthday.
2. Say 'NO' to single-use plastic bags and use cloth bags.
3. Turn off lights, fans, and taps when not in use.
CBSE Step-by-Step Marking Scheme
Planting trees
1
No plastic
1
Saving electricity and water
1
Q14
Constellations
What is a group of stars forming a recognizable pattern called? Give one example.
[2 Marks]
✅ Step-by-Step Solution & Working
A group of stars forming a recognizable pattern is called a 'Constellation'. Example: The Great Bear (Ursa Major / Saptarishi) or Orion.
CBSE Step-by-Step Marking Scheme
Constellation definition
1
Saptarishi / Great Bear example
1
Q15
Full Moon vs New Moon
What do we call the night when the Moon looks like a complete bright circle?
[1 Marks]
✅ Step-by-Step Solution & Working
The night when the Moon appears as a full bright circle is called the 'Full Moon Night' (Purnima).
CBSE Step-by-Step Marking Scheme
Full Moon (Purnima)
1
🌟 NEP 2020 Competency-Based Case Study
Practical Application Task
Analytical Task: Why is Earth called the 'Blue Planet', and what two vital resources make Earth the only known planet with life?
Evaluation & Model Answer:
Earth is called the 'Blue Planet' because about 71% (nearly three-fourths) of its surface is covered by vast oceans and seas of water, making it appear sparkling blue from space. The two vital life-supporting resources on Earth are:
1. Liquid fresh water to drink
2. Breathable atmosphere containing oxygen.
Rubric: [object Object],[object Object]