Air Around Us

Objectives (उद्देश्य):
By the end of the lesson, students will be able to:

1. Describe the composition of air (हवा की संरचना) with approximate percentages of main gases.
2. Explain the importance of air for living organisms (जीवों के लिए हवा का महत्व).
3. Identify causes and effects of air pollution (वायु प्रदूषण) and suggest simple ways to reduce it.
4. Perform simple experiments to demonstrate the presence of air.
5. Answer questions correctly in an air composition quiz.

Materials Required (आवश्यक सामग्री):

• Whiteboard/markers or blackboard/chalk
• Torch (for dust observation)
• Empty glass/plastic bottle, water, candle/matchstick (for presence of air experiment)
• Balloon, straw, plastic bottle (optional alternative experiment)
• Chart paper, sketch pens, old newspapers/magazines for cutting pictures (for discussion/poster if extended)
• Printed quiz sheets (sample provided below)
• Flashcards/pictures: oxygen mask, plants, vehicles smoke, clean vs polluted city air

---

Step 1: Introduction (परिचय) – 10 minutes

Purpose: Make students realize air is present everywhere though invisible.

• Warm-Up Activity: Ask students to:
  
  • Take a deep breath and hold it for 10 seconds.
  • "What happened? Why couldn't you hold it longer?" (क्या हुआ? इतनी देर क्यों नहीं रोक पाए?) → Lead to: We need air every moment to live – air is the invisible life-giver! (हमें हर पल जीने के लिए हवा चाहिए – हवा अदृश्य जीवनदाता है!)
• Theme Introduction: "Today we will learn what air is made of, why it is essential for all living beings, and what happens when air gets polluted." (आज हम सीखेंगे हवा किससे बनी है, सभी जीवों के लिए यह क्यों आवश्यक है, और जब हवा प्रदूषित हो जाती है तो क्या होता है।)

---

Step 2: Main Concepts (मुख्य अवधारणाएँ) – 25 minutes

Concept 1: Composition of Air (हवा की संरचना)
Air is a mixture of gases (mostly invisible).

Use this table on the board (approximate values as per NCERT/Class 6 level – dry air basis):

Note for students: Percentages are approximate; oxygen ~21%, nitrogen ~78%, rest very small.
(छात्रों के लिए नोट: प्रतिशत लगभग हैं; ऑक्सीजन ~21%, नाइट्रोजन ~78%, बाकी बहुत कम।)

Concept 2: Importance of Air for Living Organisms (जीवों के लिए हवा का महत्व)

• For animals & humans: Oxygen is needed for respiration (श्वसन) → releases energy from food. (ऑक्सीजन श्वसन के लिए जरूरी → भोजन से ऊर्जा मिलती है।)
• For plants: Carbon dioxide used in photosynthesis (प्रकाश-संश्लेषण); release oxygen. (पौधे CO₂ से भोजन बनाते हैं और ऑक्सीजन छोड़ते हैं।)
• Other uses: Wind helps pollination, seed dispersal; air pressure, burning/combustion, etc. (हवा से परागण, बीज फैलाव, दहन आदि होते हैं।)

Concept 3: Air Pollution and Its Effects (वायु प्रदूषण और प्रभाव)

• Causes (कारण):
  
  • Smoke from vehicles, factories, burning coal/wood/fuel
  • Dust from construction, fields
  • Garbage burning, stubble burning (common in Bihar/Punjab)
• Effects (प्रभाव):
  
  • Breathing problems: asthma, cough, lung diseases
  • Harm to plants: reduced growth, damaged leaves
  • Harm to animals: eye irritation, weaker health
  • Smog in cities (e.g., Delhi winters), acid rain
  • Global warming (increased CO₂)

Simple ways to reduce pollution (प्रदूषण कम करने के तरीके):

• Use public transport/cycle
• Plant trees
• Say no to crackers/burning waste
• Use CNG/auto instead of diesel

---

Step 3: Activities (गतिविधियाँ) – 35 minutes

Activity 1: Observing Dust Particles in the Air (हवा में धूल कणों का अवलोकन) – 8 minutes
Materials: Dark room + sunlight beam through window or torch.
Steps:

1. Darken classroom slightly.
2. Shine torch/sunlight beam across room.
3. Ask: "What do you see dancing in the beam?" (बीम में क्या नाचता दिख रहा है?) → Tiny dust particles – proof air carries dust/smoke/pollutants. Discussion: "These particles can enter our lungs if air is polluted." (ये कण प्रदूषित हवा में फेफड़ों में जा सकते हैं।)

Activity 2: Experiment to Show the Presence of Air (हवा की उपस्थिति दिखाने वाला प्रयोग) – 12 minutes
Simple & Safe Experiment: Candle in Inverted Glass
Materials: Glass, water in plate, lighted candle.
Steps:

1. Light candle on plate, pour some water around.
2. Cover burning candle with inverted glass.
3. Observe: Flame goes out after some time → oxygen used up.
4. Water rises inside glass → air pressure difference (outside air pushes water up). Alternative (no fire): Balloon in bottle – blow balloon inside sealed bottle (hard) vs. with hole (easy) – shows air occupies space & pressure.

Activity 3: Group Discussions on Reducing Pollution (प्रदूषण कम करने पर समूह चर्चा) – 15 minutes
Divide class into 4-5 groups.
Each group discusses (5 min):

• One major cause of air pollution in Patna/Bihar.
• Two practical ways students can reduce it at home/school. Groups present (1-2 min each). Teacher notes good ideas on board (e.g., "No idling of vehicles", "Plant neem/tulsi at school").

---

Step 4: Assessment (मूल्यांकन) – 15 minutes

Assessment Type: Air Composition Quiz (हवा की संरचना प्रश्नोत्तरी)

Quiz Format: 10 marks (mix of MCQ, fill-in, short answer). Students write in notebook/copy.

Sample Quiz Questions (with answers for teacher):

1. The major component of air is: (1 mark) a) Oxygen b) Nitrogen c) Carbon dioxide d) Water vapour Ans: b) Nitrogen (~78%)
2. Percentage of oxygen in air is approximately: (1 mark) Ans: 21%
3. Which gas do plants use to make food? (1 mark) Ans: Carbon dioxide (CO₂)
4. Fill in the blanks: (2 marks) a) Air is a mixture of gases, water vapour and ________ particles. (dust) b) We breathe in ________ and breathe out ________. (oxygen, carbon dioxide)
5. Name two effects of air pollution on human health. (2 marks) Ans: Any two: breathing difficulty, asthma, cough, lung diseases, eye irritation.
6. True or False: (2 marks) a) Air is visible. (False) b) Planting trees helps reduce air pollution. (True)
7. Short answer: Name one way you can help reduce air pollution in your daily life. (1 mark) Ans: Examples: Walk/cycle instead of car, plant trees, avoid burning leaves/plastic.

Marking: 1 mark per correct answer. Total 10. Discuss answers after collection.

---

Step 5: Conclusion and Homework (समापन और गृहकार्य) – 10 minutes

Summary (सारांश):

• Air is mostly nitrogen (78%) and oxygen (21%).
• Air is essential for breathing, burning, plant food-making.
• Pollution harms health and environment – we must protect clean air.

Homework (गृहकार्य):

1. Draw a pie-chart showing approximate composition of air (label percentages and gases).
2. Write 5 sentences on "How I can help keep the air clean in Patna." (पटना में हवा साफ रखने में मैं कैसे मदद कर सकता हूँ।)
3. Observe smoke/dust near your home/school and note one cause + one solution.