📏 Part 1: Measuring Practice

1. Use the three measuring tools to measure the objects listed below. Record your measurements in the table.

Instructions: Measure each object with a ruler, tape measure, and calipers. Record the measurement and units for each tool.

Object	Ruler Measurement	Tape Measure Measurement	Caliper Measurement	Most Accurate Tool
Pencil length	_______ cm	_______ cm	_______ mm	_____________
Book width	_______ cm	_______ cm	_______ mm	_____________
Desk length	_______ cm	_______ cm	_______ mm	_____________
Coin diameter	_______ mm	_______ mm	_______ mm	_____________

2. Which measuring tool was easiest to use for each object? Explain your reasoning.

🔄 Part 2: Unit Conversions

3. Convert the following measurements between metric units:

a) 150 mm = _______ cm

b) 2.5 m = _______ cm

c) 85 cm = _______ mm

d) 1200 mm = _______ m

e) 0.75 m = _______ mm

f) 45 cm = _______ m

4. Show your working for converting 3.2 metres to millimetres:

🎯 Part 3: Estimation and Accuracy

5. Before measuring, estimate the length of these objects. Then measure them accurately.

Object	Your Estimate	Actual Measurement	Difference
Your hand span	_______ cm	_______ cm	_______ cm
Classroom door height	_______ m	_______ m	_______ cm
Your shoe length	_______ cm	_______ cm	_______ cm

6. Circle the most appropriate tool for each measuring task:

Measuring the thickness of a coin:

Ruler

Tape measure

Calipers

Measuring the length of a football field:

Ruler

Tape measure

Calipers

Measuring the width of your textbook:

Ruler

Tape measure

Calipers

🔧 Part 4: Precision and Accuracy

7. Explain the difference between precision and accuracy in measurement:

8. Which measuring tool gives the most precise measurements? Explain why.

9. List three important rules for accurate measurement:

1. _________________________________________________

2. _________________________________________________

3. _________________________________________________

⭐ Part 5: Extension Activities

10. Advanced Challenge: Use calipers to measure internal dimensions.

Find a cylindrical object (like a tube or pipe) and measure:

External diameter: _______ mm

Internal diameter: _______ mm

Wall thickness: _______ mm

11. Real-world Application: A carpenter needs to cut timber pieces with these measurements. Convert them to the most appropriate unit:

a) 2500 mm = _______ m (for ordering timber length)

b) 4.5 cm = _______ mm (for precise cutting)

c) 0.85 m = _______ cm (for marking measurements)

12. Problem Solving: If you measured a table as 152.3 cm with calipers, 152 cm with a ruler, and 150 cm with a tape measure, which measurement is likely most accurate and why?

13. Design Challenge: Draw a diagram showing how to properly position calipers to measure the external diameter of a circular object.