Hi Michelle and fellow mom of 3 boys! We were just at the Polynesian a couple of weeks ago, and one of the best things we loved about the resort is its access to the parks. We could visit the Magic Kingdom by quick rides on either boat or monorail. When we went to Epcot, we walked over to the Ticket and Transportation Center to catch the Epcot monorail.
The volcano pool with its zero entry, slide, sand beach, and views of the Magic Kingdom was a hit for my sons. They loved discovering, too, that music is played underwater. There is a nearby sand volleyball court if your sons are interested. Make sure and ask for the list of weekly activities at the resort, too!
We stayed in Tokelau which is in close proximity to everything at the resort, and we simply stepped out onto the patio and turned left to see the fireworks. It was great on a couple of nights when we came home early, but we could still enjoy the fireworks. Also, the grounds of the resort are so lush and tropical, and at night the paths are lit with torches - very romantic!
Since your sons are sports fans, they may enjoy eating at the ESPN Club on the Boardwalk. My sons love the chance to run around at the The Boneyard play area at the Animal Kingdom as well as the Honey, I Shrunk the Kids play area at Disney's Hollywood Studios (DHS). Here are a few other of my sons' favorites: Jedi Training at DHS, the pirate cruise that launches from the Grand Floridian, the water parks, miniature golf, and Disneyquest.
Have a great trip!