Meters or yards if it's the school library, in the same building or on the same campus
as the classroom.
Kilometers or miles if it's simply the municipal library, in the same city as the classroom.
You can measure the width of your classroom using a measuring tape for accuracy. Alternatively, you could use a yardstick or a meter stick if the room is not too wide. For a quick estimate, you might use a string or a piece of chalk to mark the distance, then measure that with a ruler. If you have a laser distance measurer, that would provide a precise measurement quickly.
You would typically measure the distance around a school in meters, as this is a more precise unit of measurement for shorter distances. Kilometers are better suited for measuring longer distances.
meters
Metres or kilometres in metric; yards or miles in Imperial
Meters are used for measuring distance. For classroom lenght use meter (m). For classroom floor space use square meter (m*m or m^2). For classroom volume use cubic meter (m*m*m or m^3).
Identify the SI until you would use the measured the width of your classroom
You can measure the width of your classroom using a measuring tape for accuracy. Alternatively, you could use a yardstick or a meter stick if the room is not too wide. For a quick estimate, you might use a string or a piece of chalk to mark the distance, then measure that with a ruler. If you have a laser distance measurer, that would provide a precise measurement quickly.
METERS!!!The unit of measurement you would use to measure the width of your classroom is meters.
in feet
I would use a yardstick, a foot ruler, a tape measure, a meter stick, or a laser rangefinder to make the measurement. After I knew the distance, I could convert it into any convenient unit in order to describe it or report it to others. The most convenient metric units would be either meters or centimeters.
meters
The metric unit of the meter would be the appropriate measure of the area of classroom. Calculating area involves multiplying the length (in meters) of the classroom's length and width. Area of the classroom would be in square (^2) meters.
Meter stickI'm thinking you would use a tape measure
With a tape measure or a yard stick.
Meters
A stapler
yards