I have a long list of things to do this month in DC because there is so much to see right now. So far we've done ZooLights, the Smithsonian Holiday thing, Winternational, the Downtown Holiday Market, and the Alexandria Boat Parade.
I'd been told that ZooLights wasn't amazing so we weren't expecting anything amazing. We did have a great time at the zoo in the dark though and it was a pleasant evening. I drove in and we found parking easily (we parked and entered at the lower entrance where it's not so crowded), but getting home when rush hour was still winding down wasn't fun. But it takes a lot time to Metro in from our house so there's really not a good way to do this. I'd go again if someone else drove me home.
Winternational was fun. I got a ticket like I was supposed to, but no one was taking them and it was rather crowded. There were people from about 25 different embassies with lots of food and things to see so it was fun. The Uzbekistan line was always long, but I eat Uzbek food all the time so I didn't wait in it. I tried things from Uganda, Nepal, Uruguay, and more, and talked to the person at the Saudi Arabia stand for a while. If you go, arrive at the very beginning.
Downtown Holiday Market. This is exactly what you'd expect it to be. It's fun to poke around and you can stop at the National Portrait Gallery/American Art Museum if you want to. Some vendors are there all month and some just for a few days or weeks so you can wander through throughout the month and see different things.
Smithsonian Holiday Event. This is on the first weekend in December at several different museums. We started at the American History Museum, then went over to the Air and Space Museum where you could make some ornaments and do other projects, then went to the Museum of the American Indian for their market. It was fun, but not an amazing must do.
Boat Parade. We were first planning on going to Alexandria to see this, but then I decided there much be a better way to see the parade than to deal with the crowds that would assuredly be in Alexandria. So we tried Potomac Park and that was perfect. There were people there but it was never crowded and we had a great view of the boats. There is plenty of parking and plenty of places to watch from. You can arrive around 6 PM and bring a picnic then watch the boats when they arrive between 6:30 and 7, depending on where you are in the park. I'd definitely do this one again in that park.