Getting the Goods on Graphing

Velma Elois Rouse              DeWitt Clinton
8542 S. Elizabeth St.          6110 N. Fairfield Av.
Chicago IL 60620               Chicago IL 60659
312-723-7077                   312-534-2025

Objectives:

To graph ordered pairs in the coordinate plane
To identify ordered pairs in the coordinate plane
To write the coordinates of points shown on a plane
To create designs or pictures using ordered pairs

Materials needed:

Graph paper (3 or more sheets per student)
Rulers (1 per student)
Pencils (1 per student)
Overhead projector
Overhead projector transparencies
Maps (2 per student)

Strategy:

Give each student a map that has the index and grid markings removed.  Instruct 
the students to locate certain points.  After a brief span of time, distribute 
the maps with indexes and all markings in place.  Again, instruct the students 
to locate certain points.  Lead the students to discover the usefulness of 
grids. 

Distribute graph paper.  Have the students construct a coordinate plane.  
Demonstrate on the overhead projector.  Label the axes, stressing that the 
horizontal axis is x and the vertical axis is y.  Explain the point of origin 
and the negative and positive x and y locations.  Allow sufficient time for 
students to practice locating points and naming coordinates. 

Have the students locate ordered pairs on their graph paper and connect the 
points in order.  Plan for the connected points to form a geometric figure.

Prepare in advance a different set of ordered pairs for each student.  Plan for 
the resulting figures to coincide with a current event, holiday, or school 
program.  Display the finished graphs in a prominent place.

Performance Assessment:

Each student will create his or her own picture or design on graph paper and 
write the ordered pairs.  The ordered pairs will then be given to other 
students.  The student who created the design will be expected to correctly 
write ordered pairs that will duplicate the design.  The student who graphs the 
ordered pairs will be expected to correctly duplicate the design.  Both of these 
performances should be completed with 95% accuracy. 

Conclusion:

The students will realize that the skills they have acquired will be useful in 
many areas besides mathematics.  Other disciplines that utilize graphs are 
science, geography, economics,  and computers.  With the use of and interest in 
computers continuing to grow, students will be made aware of a career choice in 
computer-aided design (C.A.D.). 

Multicultural Statement:

Africans invented rectangular coordinates by 2650 B.C. and used them to make 
scale drawings and star-clocks in ancient Egypt.