How to Draw a Map to Scale

The Mural Method

Materials:

1.      A map with a scale in hundreds increments. (You must be able to draw on it.)

2.      2 index cards

3.      a ruler

4.      a sharp pencil.

5.      Optional: a T square ruler or a circle drawing compass.

Task #1: You will draw a grid by hand on your map.

Preparing the grid

1. Find a map of the country you want to draw.
2. On the map find the scale that tells the number of miles a certain distance is. We will deal in increments of 100, 200, or 300 for this exercise. (If you want to substitute kilometers, use the same method.)

3. I will call this measure the horizontal scale (You may turn your map so that scale measures horizontally, if necessary).
4. On an index card put two “tick” marks or notches that show the main increment for measurement.  In the case of the scale above, that increment is two hundred miles.
5. You will continuously check that your grid is correctly measured by using this measurement.

Drawing the grid

1. Put your ruler up next (and parallel) to your scale and extend the scale line to the boarders of your map.
2. Notch or “tick” each distance exactly as it is done in the original scale.
3. From each notch extend a vertical line to the bottom of the map. With your “scale checker” make sure that the distance between each line is exact at top and bottom. There are several ways to assure that lines are parallel.
4. Then notch the center vertical line and each of the end lines. Connect those notches with horizontal lines. This should create a gird of exact squares.
5. Check with your “scale checker” that each square is exact.

Creating 100 mile Increments

1. Look at your scale. If you scale is at 100-mile increments. You are finished Task # 1. If not, read below.
2. If your scale is, as above, in 200-mile increments, you must divide your boxes into 4 parts.
3. If your scale is in 300-mile increments, then you must divide your box into thirds or 9 little boxes.
4. The object is to obtain a grid that measures 100 miles on each side of the box exactly or 100 square miles.
5. Label them from left to right (only at the top) A through Z (then AA, AB, AC etc.) according to the number of boxes you have.  On the left side of your grid, label the boxes 1 through however many necessary to reach the bottom of your page. 

Task #2: Drawing your map

1. On a separate piece of paper, draw a grid of 1-inch square boxes.  Label those boxes as done in step 5, above.
2. Draw one box at a time exactly as it is in the corresponding box of the same number. For example: Read the first box as A1 ; the second horizontally as B1 and so on.
3. The map that you have just drawn will be exactly 1 inch equals 100 miles. You should be able to cut out the maps and put them together with other maps of the same scale on a larger board.

   Other Approaches

    

           From Unicef

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