Carnival Shore Excursions- Freeport

[IMKTDQT810]

I am browsing on the Shore Excursion site for Freeport.

DS (9) has never snorkeled in the ocean (only practiced once in a pool and it went so-so) and we were thinking of our first stop (Grand Turk) we do a snorkel Ex. but then I saw they offer a semi-submarine that he might enjoy more. The next day is HMC and we have our own snorkel stuff that he can play around and snorkel there (for free).

Freeport is our last port and even thought DH said he didn't want to do excursions at every port and Freeport was going to be a "ship day" and shop at the pier only I wanted to know what folks thought about the snorkel excursions that Carnival offered at this port? Just in case we change our minds after going to HMC and DS wants to snorkel one last time. Thanks!!