Overtime Elite, a private school, basketball league and media conglomerate, opened this fall in a glitzy new arena in Atlanta. The complex houses a main court where players compete against each other and other prep-school teams, practice courts, a weight room, physical therapy center, made-to-order kitchen, lounge and locker rooms. A corporate suite filled with social media producers and editors stand ready to turn everything the players are doing into entertainment content for Overtime, the sports media startup whose founders dreamed up this idea. Deeper within the arena is academic space, where teachers and administrators are trying to redesign players’ final years of high school and first years of post-secondary life to be more personalized, rigorous and relevant. And in a condensed time frame. Most days, school only lasts a few hours.