TIP: You might also want to contact your own university and see if they provide housing through their alumni.
International Student Housing:
The rates at the International Student House include breakfast and dinner daily, excluding dinner on Saturdays. No rebate is given for meals not taken at the House. There are no cooking facilities for residents, and cooking is not allowed in the rooms. All rooms are furnished with desk, chair, lamp, single bed, dresser and bookcase. Heating, air-conditioning and 13 meals weekly are included in the rates. A one-time bed linen set-up charge of $15 and an activity fee of $60 (long term) or $40 (short term) will be assessed on your first invoice. The activity fee is annually renewable. Residents may bring their own towels, or buy them from the House. In shared rooms, students do not choose their roommates, who will normally be from different countries. Men and women live in separate quarters and have separate bathrooms. Rooms do not have private bathrooms unless specified.
Rooms for 4: Main Building (women only) $700
Rooms for 3: (private bath) $783-860
Rooms for 2: Marpat Hall (men only) Main Building (women only) Van Slyck (men and women) $705-795, $785, $860-920
Rooms for 2: (private bath) $905
Single rooms: $920-1,020
The International Student House
1825 R Street, NW
Washington, DC 20009
Summer Sublets: http://www.sublet.com
These suggestions should get the ball rolling and help you concerning housing arrangements while in Washington, D.C.