How to import local folder of mp3 files as a complete playlist

I have no problems exporting an itunes playlist to a local folder of mp3 files, and I'm able to import local mp3 songs into itunes one at a time. But I can't seem to figure out how to import a local folder with many mp3s to a single itunes playlist. For example, if I have a folder of mp3s on my computer named "driving mix," I'd like to be able to create an itunes playlist named "driving mix" by importing the folder all at once.