These interactive maps are becoming more and more popular. They are amazing resources for visualizing change over time. The number of visual learners in our classrooms is growing rapidly, making these digital maps valuable teaching tools.
The latest map in this genre is based on Claudio Saint's new book West of the Revolution: An Uncommon History of 1776. It shows the gradual transfer of Indian land to the United States government between 1776 and 1887. Read all about it here.