This PowerPoint presentation covers the expansion of slavery, throughout the first 70 years of the United States. Each slide shows the breakdown of free/slave states, as well as a color-coded map. This will help students visualize the race to add new states on both sides of the issue. I use this presentation as a perfect backdrop for my explanation of the Missouri Compromise, the Compromise of 1850, and Bleeding Kansas. If you use Google software more often than Microsoft, there is a link to the same presentation in Google Slides format.