Definately add camping at Arcadia National Park in Bar Harbor, ME (pronounced Bah Hahbah, of course!).  The smell of the pine forest combines with the salt sea air - wonderful! And cooking "surf & turf" (lobstah - that you bought 5 minutes earlier at the dock - and steak) mmmm, yum!  Gorgeous rocky coastline, beautiful clear air - I think I'm homesick for New England! Nantucket's right up there, too as a fun place, but you need to go to the website listing where the toilets are, because they're far and few between!  Great bicycling on both Nantucket and The Vinyard, and you can take your bikes on the bus (I think) so you can give up at any time little legs give out.  Bike path runs right next to the beaches, so wear your bathing suits so you can pop in for a quick dip when you get hot.  And last but not least, the very northenmost part of the Cape Cod National Seashore - whales and a tiny little airport with lots of small planes going in and out make it a great kid place.