In Port from 1pm-10pm

My family will be in port from 1pm to 10pm, it will be 4 adults and 4 children (11,9,6,4). I am looking for something to do, not an excursion, as we have ours booked on other islands already. I have been looking into Mambo Beach, as a stop for a couple hours for beach time and I think the boys will like to see the Queen Emma Pontoon Bridge as well. Any other suggestions would be great!!

What did you guys decide to do? We are going this year and we have ages 2 (almost 3), 14, 31, 34.