Where to go for my Birthday Dinner?!

I'm planning out my 17th birthday which is in a couple months. I'm planning on bringing a relatively small group, me and 5 friends, plus my parents, and possibly my sister who wants to come too, to go to Madame Tusseauds in DC (we live about an hour away) and then out to eat. With the price of the wax museum, I want to go out to eat somewhere affordable, but I haven't eaten in DC in a while and I can't think of anywhere. Do you know any group friendly places we can eat where it would be around 13 dollars or less per person per entree? Thanks :)