[Kraftwerk]

Building boats is a whole other way to understand the nautical world. I would fully encourage that in a kid . You are a lucky parent if the kid is not in front of a screen all day.
Sailing is great. I sail all year 'round, race all winter ; Frostbiting it's called. (This summer has been difficult to get the time on the water oddly enough.) Sailing is a good thing on many levels. Get the kid racing. They will learn everything 10x faster. Also consider the spirit of competition: good sportsmanship is alive and well in sailboat racing, generally. It is a skill he will have for life. There is something to be said for being on the water comfortably and harnessing the wind while respecting the forces of the sea and nature. 1000x more so if the boat was built by the person sailing it.. Amazing kid you have there.