When I was a kid, my favorite museum in Paris was definitely the Navy Museum (Musée de la Marine). First the location is great, on top of the Trocadéro, facing the Eiffel Tower on the right Bank. Then inside the Museum, you can see gigantic models of sail boats, some of them several hundred years old (the model and the boat it represent were sometimes made at the same time!). You have also huge wooden sculptures that were the figurehead on the ships. There is also a real rowing yacht that belonged to Napoleon, gold and white, it's really something worth seeing!