Within the next couple of hours, Anderson and a group of current and former N.B.A. and W.N.B.A. players would be coaching the country’s best boys’ high school players at an annual camp run by the N.B.A. players’ union. For decades, this weeklong camp has served a dual purpose: to put a spotlight on top teenage prospects for scouts and to provide a training program for players eyeing coaching as a future career.