Kids are so different in what they're interested in at that age. Here are a few thoughts. You could present him with a list of options and see what sounds good.
The Bronx Zoo.
The Trenton Aquarium.
Philadelphia- lots of history.
Maybe one of the heavily-commercial franchises in NYC- one Irish woman I know was dragged by her son (about the same age) to the World Wrestling Federation shop.
Definitely a day trip to NYC. I'd recommend the ferry to lower Manhattan if it's still running.
Hiking for a day at the section of the Appalachian trail in your area. (Sorry, I forget where it is- used to live in Wyckoff but have been in Kansas for 2 years.)
Golfing, if you and he are into that.
Finally, ask your son what he liked/didn't like about his trip to France. That may give you a good idea what works and doesn't work.