⚖️ What is Mass?
Mass tells us how heavy something is. In Canada, we use the metric system:
Gram (g) → used for light objects
Kilogram (kg) → used for heavier objects
1 kilogram = 1,000 grams
🪶 Grams (g) – For Light Things
Examples of grams:
• A paperclip ≈ 1 gram
• A small apple ≈ 100–150 grams
• A slice of bread ≈ 30 grams
• A chocolate bar ≈ 50 grams
🐘 Kilograms (kg) – For Heavier Things
Examples of kilograms:
• A bag of sugar = 2 kg
• A big watermelon ≈ 5–8 kg
• Your school backpack ≈ 4–7 kg
• An average Grade 4 student ≈ 25–35 kg
🔄 Converting Between Grams and Kilograms
To change grams to kilograms → divide by 1,000
To change kilograms to grams → multiply by 1,000
2,500 grams = 2.5 kg
3.5 kg = 3,500 grams
750 grams = 0.75 kg
✏️ Let’s Practice Together, My Dear Student!
Practice 1: Choose the Best Unit
1. Mass of a pencil → grams
2. Mass of a dog → kilograms
3. Mass of a car → kilograms
Practice 2: Conversions
1. 4,000 grams = 4 kg
2. 1.5 kg = 1,500 grams
3. 750 g = 0.75 kg
Practice 3: Word Problems (Canadian Style)
1. A bag of apples has a mass of 3 kg. How many grams is that?
3,000 grams
2. You have a 2.5 kg bag of rice. You use 800 grams for dinner. How much rice is left?
2,500 g - 800 g = 1,700 grams (or 1.7 kg)
Challenge Question
Your school bag is 4.2 kg and your lunch box is 650 grams. What is the total mass?
4.2 kg + 0.65 kg = 4.85 kg
Fantastic Job, My Dear Student! 🎉
You now understand grams and kilograms very well! You can choose the right unit and convert between them.
I am so proud of you for learning the Mass unit. Next time you help in the kitchen or go grocery shopping, notice the mass written on packages!
💕 You are smart. You are kind. You can do hard things.
When you are ready, tell me the next topic (Millilitres and Litres, Perimeter, Area, or anything else) and I will create another beautiful lesson just for you!