Start the trip by exploring the Smithsonian National Museum of American History, which has an array of interactive exhibits, including the Star-Spangled Banner, Abraham Lincoln's top hat, and Thomas Jefferson's writing desk. Afterward, take a walk through the National Mall and enjoy the beauty of the outdoor space and landmarks such as the Washington Monument, World War II Memorial, and Lincoln Memorial.
The National Air and Space Museum offers an incredible collection of aviation and space artifacts, including the Wright Brothers' plane and Amelia Earhart's flight suit. Afterward, head over to the US Capitol Building to visit the world's most iconic legislative building and admire the unique architecture.
Begin the day at the Smithsonian National Zoological Park, and see over 2,000 animals, including pandas, elephants, and tigers. Afterward, head over to Georgetown and visit the famous Georgetown Cupcake. The bakery offers a variety of delicious flavors, including salted caramel, peanut butter fudge, and red velvet.
If you have more time, consider visiting other famous Washington DC sites such as the National Archives Museum or the Library of Congress. You can also check out the famous cherry blossoms around the Tidal Basin. If you have less time, consider combining the National Air and Space Museum with another museum in the area or eliminating the Georgetown Cupcake stop. Don't forget to pack comfortable walking shoes and dress appropriately for the weather.