Locating Points Using Cartesian Coordinates

Mercedes Rodriguez             Clemente Community Academy H. S.
2201 N. La Crosse Ave.         1147 N. Western Ave.
Chicago IL 60639               Chicago IL 60622
312-745-6809                   312- 534-4000

Objectives:
                  
    1. To give the coordinates of a point.
    2. To plot a point, given it's coordinates.
    3. To use the coordinate system in locating places on the map.
  
Materials Needed:

Rulers
Chicago City Maps
Graph Paper
Multicultural Handout (Rene Descartes)
Activity Sheets

Strategy:

     1. The teacher will ask the students questions concerning how they give 
directions to get from one place to another.  After discussion and finding 
different responses, pass out Chicago City maps so they show some paths on the 
map.  The teacher will ask the students which important directions they need (N, 
S, E, W). 

     2. Introduce the Cartesian Plane by drawing two number lines on the board 
intersecting at zero.  Explain information concerning the Cartesian Plane 
(origin, positives and negatives, quadrants, etc.).  Discuss the term ordered 
pair.     

     3. The teacher will assist the students in locating points on the plane, by 
giving some examples on the board. 
              
     4. The students will give the coordinates of points on the plane.
     
     5. The students will plot points on the plane.
 
     6. Given three vertices of a rectangle, students will find the coordinates 
of the fourth vertex.

     7. Make two groups play coordinates Tic-Tac-Toe on the board.  The rules of 
the game follow the regular Tic-Tac-Toe rules, except that one group must get 
four points in a line. 

Performance Assessment: 

        Draw a map of your neighborhood showing places such as schools, 
churches, post office, etc.  In giving directions, apply the skills learned 
about coordinates.  (Hint: one block = one unit, and N, S, E, W imply positive 
and negative directions).