Amtrak is a great way to travel with kids. Several times during the year they offer a deal where kids are free or half price with the purchase of an adult ticket. The train is a great option for families because you can play cards or let kids color while traveling. While there are sometimes delays, they are less common than sitting in tunnel traffic, and you can sit back and relax rather than suffer from stress. 

Our Amtrak line runs from the Norfolk station to Petersburg, Richmond, Washington D.C., New York, Hartford, and then Boston. The boys took the train with their grandmother and aunt to Richmond (Staples Mill station) and I drove our car to meet them so that we would be able to travel around Richmond with child car seats. This took about 2 hours. (On this trip we visited the Science Museum of Virginia, Lewis Ginter Botanical Gardens, and The Virginia Fine Arts Museum.) My oldest has always loved trains, but this was his first time riding a real one. He loved it and keeps asking me to travel that way again!