How To Measure Area

Levi Johnson                    James Otis
                                525 N. Armour
                                Chicago IL
                                (773) 534-6576

Objective:

The seventh graders will demonstrate an understanding of square units.

Materials Needed:
                                       
twelve inch rulers, floor space in the room at least 4 feet by 12 feet, 
rectangular objects

Strategy:

Have an individual demonstrate the amount of space covered on the floor in one 
square foot.  The student will take four twelve inch rulers placing them tip to 
tip to form a square.  The measured space is a square foot.  Ask the class how 
many individuals can stand in the square foot region.  They will immediately 
discover the answer. 

Now designate a larger square region of the floor.  Ask the class to determine 
the number of students required to fill the space (i.e., by standing within it).
Have the students make connecting squares within the region.  They continue to 
make squares with one foot sides until each person has his or her own square.  
At this point they have proved for themselves the answer to the above question. 
 
Additional application is needed to get a full and thorough insight into area. 
Give each student several surfaces to measure the area of.  The teacher should 
determine the particular units to use.  In my own lessons, measurements are done 
using either the English or metric system.  Whenever a student arrives at the 
probable answer, he or she comes to me and asks for a piece of drywall tape the 
exact size required to cover the area.  It should be noted that the teacher may 
use any kind of material suitable for covering the surface.  Some of these 
activities can be done as individual or group projects.  When the activity is 
complete students will have valid evidence of the concept of area. 
             
Performance Assessment:
     
Any student who gets the correct measurement of the area of all the objects, 
solves the problem mathematically, and is able to explain in writing what  
went on receives a grade of A.  A grade of B will be earned by students who know  
the mathematics and can almost fully explain what took place in written form or 
words.  A grade of C will be earned by those who measure accurately, can do  
most but not all of the mathematics and can give reasonable explanations about 
what took place.  Anyone else will have to repeat the exercise.                 
          
Performance Assessment:
      
Students will each measure several smaller items to find the area in square 
inches.  As they complete measurements, they come to me to request that many 
square inches of drywall tape.  Then they will cut the material into one inch 
squares to place on the object.  If their measurements and mathematics are 
correct, and they cut the paper right, they should not be under nor over in 
the amount of tape.                                             

Conclusion:
                                                                           
After following these directions and procedures to arrive at an answer, students 
should have discovered a good deal about area.