"The stepsister of nearby streets"
F St. doesn't have as much going on as some of its nearby counterparts, but it can make for an easy Plan B if where you were actually headed is too busy. The Smithsonian American Art museum is nice. There's nothing wrong with it. Because it doesn't have the masterworks like the Smithsonians on the mall, you can usually avoid the Mall crowds. If you just want to poke around a museum, this could be a good option. McCormick & Schmick's is near F and 9th, and it's good if you're looking for upper-middle end. Decent steak & oyster house. Farther along, F runs into Chinatown along the south side of the Verizon center. There are some businesses and restaurants in there, but nothing like 7th or H Streets, which are absolutely jam packed.
There's stuff to do and places to be on F St, but it's like the unloved stepchild of its nearby peers.