Since the primary goal of this trip is to make a "good first impression" of RVing to newbees, you should maximize the creature comforts of of RVing by going to a campground with hookups. Summer can be hot, and trying to sleep in a hot RV without electric for A/C might be a turn off that kills the deal. If daily showers will be expected, water and sewer hookups will be needed to avoid overfilling the gray tank. Introducing newbees to navy showers to reduce water use might not be a good first trip idea. I assume that the two families with TT are experienced RVers and can provide help and advice on set up, dumping tanks, etc.
Another thought is don't go too far from home for this first experience. IMO 200-300 miles max, especially with 5yo and younger kids, who will get tired of travel. Long drives just take away from the fun time.
If you decide to head south, my suggestion would be Frontier Town, just south of Ocean City, MD. Lots of trees there for shade and full hookups. Only a few minute drive to the beaches on Assateague.
When we head south, we go down the Garden State Parkway to the south end and take the
Cape May-Lewes Ferry to DE, then route 1 south to Ocean City. The ferry is expensive for an RV, but it's a nice ride on a nice day that the wives and kids will enjoy.
2003 Winnebago Minnie 24F - Ford E-450🙂