An excerpt:

"To make his point, he walked me into the back of one of his classrooms. It seemed to me like most other KIPP classrooms—full of focused, connected children with a magnetic teacher at the front of the room. But to Mr. Levin, there was a lot wrong with this picture.

When we left the room 20 minutes later, he rattled off four things that he had seen misfiring: an imperfect bulletin board, three students whose eyes were wandering, the teacher turning her back to face the blackboard, an incomplete reading log.

'Making all those things work is the job,' he continued. 'It's exhausting, and it's not exciting, but it's what you have to do.'"