Roatan Diving
Want an additional dive certification? Roatan and Utila are great for dive training - warm water, easy conditions, close dive sites and very inexpensive diving on both islands. You can also take ferries between islands (not super simple, but doable). Whale sharks often frequent Utila waters in season. At ~$25USD/dive, I consider this a great value destination for diving but there is not much to do topside and the marine life is not comparable to other Caribbean destinations like Cozumel, Bonaire or Cayman. Inexpensive accommodations are widely available and Utila is well known as a backpacker paradise. Watch out for biting sand flies and sand fleas in the hot month of April unless you do not mind spots on an exposed regions though :) Also, wear exposure protection when the water is warm because the jellies coming out during this time, as expected.