Schools that have switched to trimesters and block scheduling are closer to the idea, but they still hold to the terrible notion that students need to be in organized, regimented learning sessions for the entire school day. Music, art, exercise, games, and socializing activities that allow students to find an outlet for their pent-up energy is a must to help students reestablish a mental balance. Students also need opportunities to study, investigate, and work as groups outside of the traditional classroom.
To those who say that this kind of school would not prepare students for the real world, I wish to remind them that the MOST successful businesses allow for exactly this type of break and relaxation as a part of their work days and work weeks. Those companies that don't provide such mental breaks have lower employee satisfaction and higher employee turn-over even if they provide higher pay. We need to take best practices into account in all areas of our society. Saying that we need to prepare students for a harsh reality by making their lives miserable makes less sense to me than making our students happier and more successful and using those enlightened people to make the entire world a better place.