Recognize area as an attribute of plane figures and understand concepts of area measurement.
A square with side length one unit, called "a unit square," is said to have "one square unit" of area, and can be used to measure area.
A plane figure which can be covered without gaps or overlaps by n unit squares is said to have an area of n square units.
Measure areas by counting unit squares (square centimeters, square meters, square inches, square feet).
