### Use Google Maps to Find Exact Locations

Overview:
In this lesson students will find their own homes on Google maps and determine their precice latitude and longitude coordinates. They will learn how to pinpoint the locations visually and then move north, east, south, or west on the map by changing latitude and longitude values.

1. Explain to students that when we look up the latitude and longitude for a given town the coordinates will be centered on a particular place in that town, such as the post office or government center. (You can find your town's latitude and longitude using one of the online latitude/longitude look-up resources.) Using Google Maps it's possible to find the exact coordinates of other places such as our school or own homes.

2. Start by estimating the coordinates of your town using a globe (or map with latitude and longitude lines). Make your first estimate in whole numbers.

Here's a example: These are the coordinates you might estimate if you lived near at the monarch butterfly sanctuaries in Mexico:

• Latitude = 19 North
• Longitude = 100 West

3. To use Google Maps you will need to put your values exactly like this format: 19, -100

Notice these things: a) there's comma between the latitude and longitude values, b) we don't use "North" or "West", and c) the longitude value is a negative number because it's the western hemisphere.

4. Now go to Google Maps and put your latitude and longitude into the search box. Look at the Google map carefully and figure out which direction you need to move to find your school or house. (You must use "decimal degree" format*.)

5. You can move the map north/south by editing the latitude; you can move the map east/west by editing the longitude. (Let students discover that the map moves north when you make the latitude higher, south when lower; west when you make the longitude higher and east when you make it lower.)

6. After students have learned how to use Google Maps, they can challenge one another to navigate to a familiar place using latitude and longitude coordinates. For example, they can find the exact latitude and longitude of their town library, town hall, a nearby shopping center or favorite athletic center.

*Example of Decimal Degree Fomat: If you're having trouble with the latitude and longitude format, start with this example. The link below starts the map in Mexico at the monarch butterfly winter sanctuary near Angangueo. You will see that the latitude and longitude are in decimal degree format. 19.685, -100.29

A Note About Degrees and Distances
As you can see from the sketch to the right, latitude lines are equidistant but longitude lines are not. The distance between longitude lines is much greater at the equator and much less at the poles. Here are rough distances for degrees latitude:

Degrees (latitude) and distance (miles )

• 1 degree = 69 miles
• .1 degrees = 6.9 miles
• .01 degrees = .69 miles (3,642 feet)
• .001 degrees - .069 miles (364 feet)