You can't miss the obelisk that is the Washington Memorial. At the eastern base, keep heading east towards the Lincoln Memorial. Just before you reach the Lincoln Memorial, make a right and you're at the Wall. It's partially hidden among a grove of trees, but well marked.
Go early or the crowds will be overwhelming
The National Mall in Washington, DC is a great draw as the cherry blossoms emerge. Tucked into the northeast corner of the Mall, next to the much larger Lincoln Memorial is the Wall, the memorial to those lost during the Vietnam Conflict. Engraved on the wall are all the names of soldiers who lost their lives. Amidst the names are groups of school children (reflected here) who rush about.