Viewing the Cherry Blossoms
If the Mall is too much for you at cherry-blossom time (me, too!) there's a quiet suburban neighborhood that's a great alternative for cherry-blossom viewing. The Kenwood neighborhood of Bethesda gets lots of press - and way more cars than it can handle on the weekends.
The National Arboretum is another great alternative. It offers 70+ cherry tree types and some awesome views of the Capitol Columns.