No, there aren't teens only shore excursions on RCI. I too have a large spread in ages between my kids' ages and find choosing shore excursions challenging. Sometimes I will do something with my 10 year old while my husband will do something more appropriate with our toddler. Taking a cab to the beach with your family works well since many CAribbean beaches have water sports that your older one may be interested in.
Luisa Frey Gaynor
Family Cruise Editor