The pool is mostly still at the Naples YMCA on a mid-October afternoon. Golden highlights of light flicker on its surface, welcoming athletes into the water. Answering its beckoning, eighth-grader Max Lindemann of the Community School leaps into the air, flipping and twisting. He enters the water, and the surface begins to move vigorously, dancing into a tube of bubbles that follows his path to the depths of the tank. This cycle is repeated as Lindemann practices his dives again and again for the upcoming District 10 swimming and diving meet.