Costa Rica and El Salvador recommendations?


Rendezvous Conspiracy
In 7 days I'm hopping on a ship and headed to Puntarenas, Costa Rica and La Union, El Salvador. Also Stopping in Montego Bay, Jamaica. I wont have too much time in any one port, this is a training cruise that I am doing for school.

I was wondering if anyone has any advice or recommendations as to stuff to do and things to see. I'd like to avoid the tourist traps and such, much more interested in the "secret spots".

I appreciate anything you guys have!

Here's a link that shows the voyage...