This one should be easy. I just can't figure out what to search for...
For this one solution I created a unit test project, and I've been adding unit tests frantically. When I went back to try to run the original project after making all the unit tests pass I realized that I couldn't figure out how to debug the original project.
In other words, every time I try to "debug" (e.g., by pressing F5), Visual Studio will run the unit tests. So the question is how do I run various projects in a single solution? How do I select which one will run when I want it to?