When Leslee Fritz moved with her son, Dustin, to a suburb of Lansing, Mich., she found Wednesdays were more than just the middle of the week. In Holt Public Schools, every Wednesday is time for teachers’ professional development, and that means the students’ day is shorter by two hours to allow it. “I asked a lot of parents” about the unusual schedule, Fritz recalled. “They shrugged and said, ‘That’s the way it’s always been.’” Through two decades and three superintendents, Holt has stuck with a system of job-embedded professional learning time that many individual schools, never mind districts, find hard to get started. What has sustained the system is a culture in which teachers have claimed their time and created the support they needed both