📏 Measurement - Length, Weight, and Capacity

What is Measurement?

Measurement is a way to find out how big, heavy, or full something is.

It helps us understand the size or amount of things around us using numbers and units!

Three Main Types of Measurement

1️⃣ Length (Size)

Length tells us how long or how tall something is.

Length: How long an object is (left to right)
Height: How tall an object is (bottom to top)
Width: How wide an object is (side to side)

2️⃣ Weight (Mass)

Weight tells us how heavy or how light something is.

3️⃣ Capacity (Volume)

Capacity tells us how much liquid a container can hold.

It answers: "Does it hold more or less?"

⚖️ Comparing Objects

Long and Short (Length)

We compare the length of objects to see which is longer or shorter.

Longer: The object that measures more from end to end
Shorter: The object that measures less from end to end
Same Length: Both objects measure the same

Example: A pencil is shorter than a ruler.
If pencil = \(15\) cm and ruler = \(30\) cm, then \(15 < 30\)

Tall and Short (Height)

We compare the height of objects to see which is taller or shorter.

Taller: The object that measures more from bottom to top
Shorter: The object that measures less from bottom to top
Same Height: Both objects measure the same

Example: A tree is taller than a flower.
If tree = \(5\) meters and flower = \(50\) cm, then \(5 \text{ m} > 50 \text{ cm}\)

Light and Heavy (Weight)

We compare the weight of objects to see which is heavier or lighter.

Heavier: The object that weighs more
Lighter: The object that weighs less
Same Weight: Both objects weigh the same

Example: A feather is lighter than a book.
If feather = \(5\) grams and book = \(500\) grams, then \(5 < 500\)

Holds More or Less (Capacity)

We compare the capacity of containers to see which holds more or less liquid.

Holds More: The container that can hold more liquid
Holds Less: The container that can hold less liquid
Same Capacity: Both containers hold the same amount

Example: A bucket holds more than a cup.
If bucket = \(10\) liters and cup = \(250\) ml, then \(10 \text{ L} > 250 \text{ mL}\)

🔧 Non-Standard Units of Measurement

What are Non-Standard Units?

Non-standard units are everyday objects we use to measure things when we don't have rulers or scales!

Examples: paper clips, cubes, hands, feet, coins, crayons, blocks

Rules for Measuring with Objects

Use the same object: All objects must be the same size
Start at the edge: Begin measuring from one end
No gaps or overlaps: Objects must touch but not overlap
Measure in a straight line: Keep objects lined up straight
Count carefully: Count all the objects used

Common Non-Standard Units

📎 Paper clips
🧊 Unifix cubes or blocks
🖍️ Crayons
🪙 Coins
✋ Hands or feet
🍬 Small candies or beans
✏️ Pencils or sticks

Measurement Formula

Length = Number of Objects Used

Example: A book is \(8\) paper clips long.
This means it takes \(8\) paper clips to measure from one end to the other!

📐 Standard Units of Measurement

Length/Height Units

Standard units for measuring length are the same everywhere!

Metric System (Most Common):

• Millimeter (mm): Very small (thickness of a coin)
• Centimeter (cm): Small (width of a finger)
• Meter (m): Large (length of a big step)
• Kilometer (km): Very large (long distances)

Important Formulas:

\(1 \text{ meter} = 100 \text{ centimeters}\)
\(1 \text{ m} = 100 \text{ cm}\)

\(1 \text{ centimeter} = 10 \text{ millimeters}\)
\(1 \text{ cm} = 10 \text{ mm}\)

\(1 \text{ kilometer} = 1000 \text{ meters}\)
\(1 \text{ km} = 1000 \text{ m}\)

Weight Units

Standard units for measuring weight (mass):

Metric System:

• Milligram (mg): Very light (grain of salt)
• Gram (g): Light (paper clip weight)
• Kilogram (kg): Heavy (bag of sugar)

Important Formulas:

\(1 \text{ kilogram} = 1000 \text{ grams}\)
\(1 \text{ kg} = 1000 \text{ g}\)

\(1 \text{ gram} = 1000 \text{ milligrams}\)
\(1 \text{ g} = 1000 \text{ mg}\)

Capacity Units

Standard units for measuring how much liquid a container holds:

Metric System:

• Milliliter (mL): Small amount (a spoonful)
• Liter (L): Large amount (water bottle)

Important Formula:

\(1 \text{ liter} = 1000 \text{ milliliters}\)
\(1 \text{ L} = 1000 \text{ mL}\)

🔨 Measuring Tools

Tool Name	What It Measures	When to Use It	Best For
Ruler	Length/Height	Short, straight objects	Pencils, books, paper
Yardstick/Meter Stick	Length/Height	Long, straight objects	Tables, desks, doors
Measuring Tape	Length/Height	Curved or flexible objects	Waist, cloth, round objects
Balance Scale	Weight	Comparing weights	Fruits, vegetables, small items
Weighing Scale	Weight	Finding exact weight	People, bags, heavy objects
Measuring Cup	Capacity	Small liquid amounts	Cooking, baking
Measuring Jug	Capacity	Large liquid amounts	Water, juice, milk

How to Choose the Right Tool

Small + Straight → Use a ruler
Long + Straight → Use a meter stick
Curved + Flexible → Use a measuring tape
How heavy? → Use a scale or balance
How much liquid? → Use a measuring cup or jug

📏 How to Measure Using a Centimeter Ruler

Step-by-Step Guide

Find Zero (0): The ruler always starts at \(0\) on one end
Line Up the Object: Place the object so one end is at \(0\)
Keep It Straight: The object must be straight along the ruler edge
Look at the Other End: See where the object ends on the ruler
Read the Number: The number at the end tells you the length
Write the Unit: Always write "cm" after the number!

Understanding the Ruler

📏 Long lines with numbers = Centimeters (cm)
📏 Short lines between = Millimeters (mm)
📏 10 small lines = \(1\) centimeter
📏 Each small line = \(1\) millimeter

Example Measurement

Problem: A crayon starts at \(0\) and ends at \(7\).
Answer: The crayon is \(7\) centimeters long.
We write: Length = \(7 \text{ cm}\)

⚠️ Common Mistakes to Avoid

❌ Starting from \(1\) instead of \(0\)
❌ Not lining up the object straight
❌ Reading the wrong side of the ruler
❌ Forgetting to write "cm" after the number
❌ Measuring from the middle of the ruler

📊 Comparing Size, Weight & Capacity

Measurement Type	Comparison Words	Symbol	Example
Length	Longer, Shorter, Same	\(>\), \(<\), \(=\)	\(15 \text{ cm} > 10 \text{ cm}\)
Height	Taller, Shorter, Same	\(>\), \(<\), \(=\)	\(120 \text{ cm} > 100 \text{ cm}\)
Weight	Heavier, Lighter, Same	\(>\), \(<\), \(=\)	\(2 \text{ kg} > 500 \text{ g}\)
Capacity	Holds More, Holds Less, Same	\(>\), \(<\), \(=\)	\(1 \text{ L} > 500 \text{ mL}\)

📝 Important Formulas Summary

Length Conversions:

\(1 \text{ m} = 100 \text{ cm}\)
\(1 \text{ cm} = 10 \text{ mm}\)
\(1 \text{ km} = 1000 \text{ m}\)

Weight Conversions:

\(1 \text{ kg} = 1000 \text{ g}\)
\(1 \text{ g} = 1000 \text{ mg}\)

Capacity Conversions:

\(1 \text{ L} = 1000 \text{ mL}\)

Comparison Symbols:

\(>\) means "greater than" (more/longer/heavier)
\(<\) means "less than" (less/shorter/lighter)
\(=\) means "equal to" (same)

💡 Quick Learning Tips

✓ Always start measuring from zero (\(0\))
✓ Use the same unit when comparing (don't mix cm and m)
✓ Non-standard units: Objects must be the same size
✓ Line up objects straight with no gaps or overlaps
✓ Choose the right tool for the job (ruler for small, tape for curved)
✓ Always write the unit after the number (cm, kg, L)
✓ Remember: \(1\) m = \(100\) cm, \(1\) kg = \(1000\) g, \(1\) L = \(1000\) mL
✓ Practice with real objects at home and school!