The Road Scholar senior tour company has an elaborate and expensive 4 day tour. Expensive because of being a full-service bus tour and talks from experts.
Go to the itinerary/schedule drop-down and read the details. There may be something about how they lay out their schedule that's efficient to copy. And you might find some of their stops of interest.
There may also be a Chesapeake Bay science for families tour on this site.
From what I've heard, you need to be well prepared re: biting insects.
https://www.roadscholar.org/find-an-adventure/10545/Island-Adventure-Discover-Chincoteague-and-Assateague-Islands/itinerary/