As I have written in the past my favorite feature of Google’s My Maps (now available to access from Google Drive) is the option to create multiple layers of placemarks in each of your custom maps. Here are five ideas for creating multiple layer maps in your classroom.

• Multiple layers can be used for showing data differences on a year over year or month over month basis. 
• You can display the same data with different base layers for comparison. 
• Students working collaboratively on a map can be responsible for editing their own layers on the same map. 
• If you’re using My Maps to have students create literature trips (look here for inspiration), they can create a different layer for each chapter of a book. 
• Students mapping the history of an event like the U.S. Civil War can create a different layer for each year of the war.