First Landing State Park is, as was said earlier, your best choice, but it is very popular and hard to get into during the summer. First Landing State Park
It has a wonderful maritime forest and nature area with a bike trail that dumps you out in downtown Va. Beach. It is close to some of the best seafood restaurants in the area. It's beach looks out on the entrance to Hampton Roads and the mouth of the Chesapeake Bay so ship watching is a great way to spend a day at the beach.
South of Va. Beach on General Booth Blvd. are Holiday Trav-l- Park.
Holiday Travel - Virginia Beach
and the KOA Virginia Beach KOA | Camping in Virginia | KOA Campgrounds
I prefer the travel park because there is a back road out to a market and a bicycle path that takes you to the oceanfront (right past the aquarium). However, as you might suspect, in either of these you will be packed in cheek-by-jowl with your thousand new best friends and their lovely children.
Try for First Landing.