Downtown Disney has Disney Quest, if you add water parks and more feature to your tickets. My ds is 13 & has always loved it.
Boardwalk Hotel,across the lake from you, has entertainers that roam the lobby in the evenings.
Your hotel will likely have kid's activities planned. I would check.
Buy ponchos & umbrellas before you leave home. Wander through Epcot. Mexico is inside the pyramid.