I'd do everything at home before you go but the dives
Hubby did the beginners resort dive a few times several years ago before we found Couples where all you had to do was a swim test & some practice in the pool & they took you on a shallow dive. (I'm not sure how Couples does it for newbie divers who want to try it before they get certified but think it's similar.) He liked it so much that he decided to get certified. He did the classes at home at a local dive shop in their pool, did all the tests there also but did his dives in Jamaica to finish it off & get his certification.
This is just my opinion - It seems like a lot of class time & study time to waste precious vacation time - especially if your SO isn't doing the class too. They are going to be on their own a lot while you're in class. When we see these people at the resort having to be in class or sitting around studying or taking their tests we always feel sorry that they are missing out on all the resort has to offer when they could have gotten that part of it out of the way at home.