Understanding Length and Distance
What is Length?
Length is the measurement of how long or far something is. It tells us the distance from one point to another. We use length to measure things like how tall you are, how long your pencil is, or how far you walk to school!
The Four Main Units of Length
In the metric system, we use four main units to measure length. Each one is perfect for measuring different sized things!
Millimeter (mm)
Very tiny things:
• Thickness of a credit card
• Width of a grain of rice
• Pencil lead thickness
Centimeter (cm)
Small things:
• Width of your fingernail
• Small paperclip
• Length of a crayon
Meter (m)
Medium/large things:
• Floor to doorknob
• Your height
• Width of a door
Kilometer (km)
Very long distances:
• 10-15 minute walk
• Between neighborhoods
• Distance to school