Loft mountain was a great introduction to camping for our 5 and 2 yo. It's car camping, so your packed up car is steps away, and 30 seconds more walking brings you to potable water and fully functioning bathrooms. A campstore stocked with any supplies you may have forgot, firewood and even great local beer is a 30 second drive from your campsite. There are even showers, if it gets to that point!
Our campsite had a path connecting to the Appalachian trail, which runs from Georgia to Maine - it's interesting to see backpackers passing on the trail and the kids learned to ask "how long have you been out". Some since March! This cool memorial day week-end was the perfect time to go, with no bugs and just slighlty cold nights that made sleeping in a little more inviting. We shared our site with another family and split meal prep which worked out great. The kids brought scooters to push around the paved loop road. With a 2 year old, some vigilance was necessary for the loop road as well as a few spots with cliffs when on the Appalachian Trail - but overall the site is really kid-friendly.
The activites ranged from hiking to waterfalls, sunset watching, stopping for ice cream at the campstore, ranger talks about birds and wildlife in the park and generally hanging around the campfire. The drive from Takoma Park was just under 3 hours. We got their on a Thursday of the Memorial Day weekend and obtained a great site without reservations. Otherwise, we noticed a long line of cars unable to get it due to full capacity - so a reservation would be wise: http://www.recreation.gov/camping/loft-mountain-campground/r/campgroundDetails.do?contractCode=NRSO&parkId=70852
View Parent Compass D.C. in a larger map
We stopped for lunch on the way there at the renowned red-truck bakery, rated one of the 50 best in the country! Order your sandwiches a day ahead as they are so busy they may run out!
View Parent Compass D.C. in a larger map