No crowds on weekdays, best within 2 hours of D.C.
Slow chairlifts, not much variety
There are only three reasonable day trip skiing options for people in D.C., and Whitetail is the best. (The others are Ski Liberty and Ski Roundtop -- all three are run by the same company).
It's a small mountain and there aren't a ton of trails, but it's enough to keep you busy and having fun for several hours. The three black diamond slopes are quick thrills -- not particularly long or challenging, but enjoyable -- and there's a couple of fun blues.
I do question whether this place would be worth bearing the weekend crowds/prices for, particularly if you're going to be using the beginner slopes. If you want to go, best to play hooky on a workday. I've had the luxury of being able to visit on weekdays, when there are very few crowds (you'll sometimes have an entire slope to yourself, which is a wonderful feeling). The four-hour lift ticket is also a nice, relatively affordable option.
The drive from D.C. is less than two hours, and involves some nice scenery from Frederick, Md. northward. The area immediately around Whitetail is rural, and the views from the slopes are decent.