In Montego Bay Jamaica, we went to Sunset Beach Resort and bought a day pass. It cost $40/adults and $20/children. That covered all food, drinks, alcohol, pools, water park/water slides, non motorized water toys. We had a great time there. The food was really good and the place was so beautiful. The taxi ride from the ship was about $8 for all three of us.
http://www.sunsetbeachresort.com/